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# Scientific Publications¶

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 Dipankar Saha & Santanu Mahapatra, Analytical insight into the lattice thermal conductivity and heat capacity of monolayer MoS2, Physica E: Low-Dimensional Systems and Nanostructures, Vol. 83 pp. 455--460 (2016) Acoustic phonon,First-principles calculations,Lattice thermal conductivity,Monolayer MoS2,Two dimensional transition-metal dichalcogenides,area:2dmat,area:tmd 2dmat,tmd Abstract: We report, a detailed theoretical study on the lattice thermal conductivity of a suspended monolayer MoS2, far beyond its ballistic limit. The analytical approach adopted in this work mainly relies on the use of Boltzmann transport equation (BTE) within the relaxation time approximation (RTA), along with the first-principles calculations. Considering the relative contributions from the various in-plane and out-of-plane acoustic modes, we derive the closed-form expressions of the mode specific heat capacities, which we later use to obtain the phonon thermal conductivities of the monolayer MoS2. Besides finding the intrinsic thermal conductivity, we also analyse the effect of the phonon-boundary scattering, for different dimensions and edge roughness conditions. The viability of the semi-analytic solution of lattice thermal conductivity reported in this work ranges from a low temperature (T???30K) to a significantly high temperature (T???550K), and the room temperature (RT) thermal conductivity value has been obtained as 34.06Wm-1K-1 which is in good agreement with the experimental result. BibTeX: @article{Saha2016, title = {Analytical insight into the lattice thermal conductivity and heat capacity of monolayer MoS2}, author = {Saha, Dipankar and Mahapatra, Santanu}, journal = {Physica E: Low-Dimensional Systems and Nanostructures}, publisher = {Elsevier}, volume = {83}, pages = {455--460}, year = {2016}, keywords = {Acoustic phonon,First-principles calculations,Lattice thermal conductivity,Monolayer MoS2,Two dimensional transition-metal dichalcogenides,area:2dmat,area:tmd}, area = {2dmat,tmd} doi = {10.1016/j.physe.2016.01.013}, }  Dipankar Saha & Santanu Mahapatra, Atomistic modeling of the metallic-to-semiconducting phase boundaries in monolayer MoS2, Applied Physics Letters, Vol. 108 pp. 253106 (2016) Density functional theory,Metal phase transitions,MoS2,Monolayers,Schottky barriers,Transistors,area:2dmat,area:tmd 2dmat,tmd Abstract: Recent experimental demonstration on the coexistence of metallic and semiconducting phases in the same monolayer MoS2 crystal has attracted much attention for its use in ultra-low contact resistance-MoS2 transistors. However, the electronic structures of the metallic-to-semiconducting phase boundaries, which appear to dictate the carrier injection in such transistors, are not yet well understood. In this letter, interfacing the 2H and 1T′ polytypes appropriately, we first model the “beta” (β) and the “gamma” (γ) phase boundaries, and demonstrate good agreement with experiential results. We then apply first-principles based density functional theory to calculate the electronic structures for those optimized geometries. We further employ non equilibrium Green's function formalism to evaluate the transmission spectra and the local density of states (LDOS) in order to assess the Schottky barrier nature of the phase boundaries. Our study reveals that while the γ boundary yields p-type Schottky barrier, the β boundary leads to the distinct symmetric Schottky barrier with an atomically sharp transition region. This understanding could be useful for designing high performance transistors using phase-engineered MoS2 crystals. BibTeX: @article{Saha2016b, title = {Atomistic modeling of the metallic-to-semiconducting phase boundaries in monolayer MoS2}, author = {Saha, Dipankar and Mahapatra, Santanu}, journal = {Applied Physics Letters}, volume = {108}, pages = {253106}, year = {2016}, keywords = {Density functional theory,Metal phase transitions,MoS2,Monolayers,Schottky barriers,Transistors,area:2dmat,area:tmd}, area = {2dmat,tmd} doi = {10.1063/1.4954257}, }  Ming Qiu, Yuanyuan Xie, Xianfeng Gao, Jianyang Li, Yelin Deng, Dongsheng Guan, Lulu Ma & Chris Yuan, Band gap opening and semiconductor–metal phase transition in (n, n) single-walled carbon nanotubes with distinctive boron–nitrogen line defect, Phys. Chem. Chem. Phys., Vol. 18 pp. 4643--4651 (2016) SWCNT,area:nanotubes nanotubes Abstract: Band gap opening and modulating are critical in dictating the functionalities of single walled carbon nanotubes (SWCNTs) in a broad array of nano-devices. Using first-principles density functional theory calculations, a class of semiconducting armchair SWCNTs with a distinctive BN line defect are studied, showing a super capacity to open the band gap of (4, 4) SWCNT to as large as 0.86 eV, while the opened band gap are found decreasing with the increasing diameters of SWCNTs. The opened band gap of SWCNTs can also be successfully modulated through both mechanical and electrical approaches by applying compressive uniaxial strain and electric field. This study provides novel insights into the large band gap opening and modulating of SWCNTs and could be useful in facilitating future applications of SWCNTs in electronic, optical and thermoelectric devices. BibTeX: @article{Qiu2016, title = {Band gap opening and semiconductor–metal phase transition in (n, n) single-walled carbon nanotubes with distinctive boron–nitrogen line defect}, author = {Qiu, Ming and Xie, Yuanyuan and Gao, Xianfeng and Li, Jianyang and Deng, Yelin and Guan, Dongsheng and Ma, Lulu and Yuan, Chris}, journal = {Phys. Chem. Chem. Phys.}, publisher = {Royal Society of Chemistry}, volume = {18}, pages = {4643--4651}, year = {2016}, keywords = {SWCNT,area:nanotubes}, area = {nanotubes} doi = {10.1039/C5CP06853C}, }  Anuja Chanana & Santanu Mahapatra, Density functional theory based study of chlorine doped WS2-metal interface, Applied Physics Letters, Vol. 108(10), pp. 103107 (2016) Band gap,Charge transfer,Doping,Gold,Interface structure,area:2dmat,area:tmd 2dmat,tmd Abstract: Investigation of a TMD-metal interface is essential for the effective functioning of monolayer TMD based field effect transistors (FETs). In this work, we employ Density Functional Theory (DFT) calculations to analyze the modulation of the electronic structure of monolayer WS2 with chlorine doping and the relative changes in the contact properties when interfaced with gold and palladium. We initially examine the atomic and electronic structures of pure and doped monolayer WS2 supercell and explore the formation of mid gap states with band splitting near the conduction band edge. Further we analyze the contact nature of the pure supercell with Au and Pd. We find that while Au is physiosorped and forms n-type contact, Pd is chemisorped and forms p-type contact with a higher valence electron density. Next, we study the interface formed between the Cl-doped supercell and metals and observe a reduction in the Schottky barrier height (SBH) in comparison to the pure supercell. This reduction found is higher for Pd in comparison to Au which is further validated by examining the charge transfer occurring at the interface. Our study confirms that Cl doping is an efficient mechanism to reduce the n-SBH for both Au and Pd which form different types of contact with WS2. BibTeX: @article{Chanana2016, title = {Density functional theory based study of chlorine doped WS2-metal interface}, author = {Chanana, Anuja and Mahapatra, Santanu}, journal = {Applied Physics Letters}, volume = {108}, number = {10}, pages = {103107}, year = {2016}, keywords = {Band gap,Charge transfer,Doping,Gold,Interface structure,area:2dmat,area:tmd}, area = {2dmat,tmd} doi = {10.1063/1.4943267}, }  Z.Q. Fan, Z.H. Zhang, X.Q. Deng, G.P. Tang, C.H. Yang, L. Sun & H.L. Zhu, Effect of electrode twisting on electronic transport properties of atomic carbon wires, Carbon, Vol. 98 pp. 179--186 (2016) CONDUCTANCE,DEVICES,GRAPHENE NANORIBBONS,JUNCTIONS,LEVEL,MOLECULES,NANOTUBES,NANOWIRES,NEGATIVE DIFFERENTIAL RESISTANCE,area:graphene graphene Abstract: We investigate the electron transport properties in atomic carbon wires between two zigzag graphene nanoribbon (ZGNR) electrodes by applying nonequilibrium Green's functions in combination with the density-functional theory. It shows that the ZGNR electrode twisting can modulate the conductance of the atomic carbon wire-graphene junctions remarkably. Typical currents of devices with odd carbon wires are much higher than currents of devices with even carbon wires to exhibit even-odd behavior. The negative differential resistance behaviors are only found in the devices with odd carbon wires. When the right ZGNR electrode is twisted, the curvatures of the current-voltage characteristics change remarkably upon twisted angles. The current will decrease by up to 5 orders of magnitude when the twisted angle reaches to 90°. That means the atomic carbon wire-graphene junctions can be made as a mechanical switching. BibTeX: @article{Fan2016, title = {Effect of electrode twisting on electronic transport properties of atomic carbon wires}, author = {Fan, Z. Q. and Zhang, Z. H. and Deng, X. Q. and Tang, G. P. and Yang, C. H. and Sun, L. and Zhu, H. L.}, journal = {Carbon}, publisher = {Elsevier Ltd}, volume = {98}, pages = {179--186}, year = {2016}, keywords = {CONDUCTANCE,DEVICES,GRAPHENE NANORIBBONS,JUNCTIONS,LEVEL,MOLECULES,NANOTUBES,NANOWIRES,NEGATIVE DIFFERENTIAL RESISTANCE,area:graphene}, area = {graphene} doi = {10.1016/j.carbon.2015.11.011}, }  G.R. Berdiyorov, F. El-Mellouhi, M.E. Madjet, F.H. Alharbi, F.M. Peeters & S. Kais, Effect of halide-mixing on the electronic transport properties of organometallic perovskites, Solar Energy Materials and Solar Cells, Vol. 148 pp. 2--10 (2016) Density functional theory,Electronic transport,Green's functions,Hybrid perovskite,area:interfaces interfaces Abstract: Using density-functional theory in combination with the nonequilibrium Green's function formalism, we study the effect of iodide/chloride and iodide/bromide mixing on the electronic transport in lead based organometallic perovskite CH3NH3PbI3, which is known to be an effective tool to tune the electronic and optical properties of such materials. We found that depending on the level and position of the halide-mixing, the electronic transport can be increased by more than a factor of 4 for a given voltage biasing. The largest current is observed for small concentration of bromide substitutions located at the equatorial sites. However, full halide substitution has a negative effect on the transport properties of this material: the current drops by an order of magnitude for both CH3NH3PbCl3 and CH3NH3PbBr3 samples. BibTeX: @article{Berdiyorov2016e, title = {Effect of halide-mixing on the electronic transport properties of organometallic perovskites}, author = {Berdiyorov, G.R. and El-Mellouhi, F. and Madjet, M.E. and Alharbi, F.H. and Peeters, F.M. and Kais, S.}, journal = {Solar Energy Materials and Solar Cells}, publisher = {Elsevier}, volume = {148}, pages = {2--10}, year = {2016}, keywords = {Density functional theory,Electronic transport,Green's functions,Hybrid perovskite,area:interfaces}, area = {interfaces} doi = {10.1016/j.solmat.2015.11.023}, }  G.R. Berdiyorov, H. Bahlouli & F.M. Peeters, Effect of substitutional impurities on the electronic transport properties of graphene, Physica E: Low-dimensional Systems and Nanostructures, Vol. 84 pp. 22--26 (2016) Density functional,Doping,Graphene,Transmission,area:graphene graphene Abstract: Density-functional theory in combination with the nonequilibrium Green's function formalism is used to study the effect of substitutional doping on the electronic transport properties of hydrogen passivated zig-zag graphene nanoribbon devices. B, N and Si atoms are used to substitute carbon atoms located at the center or at the edge of the sample. We found that Si-doping results in better electronic transport as compared to the other substitutions. The transmission spectrum also depends on the location of the substitutional dopants: for single atom doping the largest transmission is obtained for edge substitutions, whereas substitutions in the middle of the sample give larger transmission for double carbon substitutions. The obtained results are explained in terms of electron localization in the system due to the presence of impurities. BibTeX: @article{Berdiyorov2016h, title = {Effect of substitutional impurities on the electronic transport properties of graphene}, author = {Berdiyorov, G.R. and Bahlouli, H. and Peeters, F.M.}, journal = {Physica E: Low-dimensional Systems and Nanostructures}, publisher = {Elsevier}, volume = {84}, pages = {22--26}, year = {2016}, keywords = {Density functional,Doping,Graphene,Transmission,area:graphene}, area = {graphene} doi = {10.1016/j.physe.2016.05.024}, }  Xin Mei Li, Meng Qiu Long, Li Ling Cui, Kai Wei Yang, Dan Zhang, Jia Feng Ding & Hui Xu, Effects of line defects on spin-dependent electronic transport of zigzag MoS2 nanoribbons, AIP Advances, Vol. 6(1), pp. 015015 (2016) Electrodes,Molybdenum,Negative resistance,Transport properties,Vacancies,area:2dmat,area:tmd,transmission pathways 2dmat,tmd Abstract: The nonlinear spin-dependent transport properties in zigzag molybdenum-disulfide nanoribbons (ZMNRs) with line defects are investigated systematically using nonequilibrium Green's function method combined with density functional theory. The results show that the line defects can enhance the electronic transfer ability of ZMNRs. The types and locations of the line defects are found critical in determining the spin polarization and the current-voltage (I-V) characteristics of the line defected ZMNRs. For the same defect type, the total currents of the ribbons with the line defects in the centers are lager than those on the edges. And for the same location, the total currents of the systems with the sulfur (S) line defect are larger than the according systems with the molybdenum (Mo) line defect. All the considered systems present magnetism properties. And in the S line defected systems, the spin reversal behaviors can be observed. In both the spin-up and spin-down states of the Mo line defected systems, there are obvious negative differential resistance behaviors. The mechanisms are proposed for these phenomena. (C) 2016 Author(s). BibTeX: @article{Li2016, title = {Effects of line defects on spin-dependent electronic transport of zigzag MoS2 nanoribbons}, author = {Li, Xin Mei and Long, Meng Qiu and Cui, Li Ling and Yang, Kai Wei and Zhang, Dan and Ding, Jia Feng and Xu, Hui}, journal = {AIP Advances}, volume = {6}, number = {1}, pages = {015015}, year = {2016}, keywords = {Electrodes,Molybdenum,Negative resistance,Transport properties,Vacancies,area:2dmat,area:tmd,transmission pathways}, area = {2dmat,tmd} doi = {10.1063/1.4941041}, }  G.R. Berdiyorov, F. El-Mellouhi, M.E. Madjet, F.H. Alharbi & S.N. Rashkeev, Electronic transport in organometallic perovskite CH3NH3PbI3: The role of organic cation orientations, Applied Physics Letters, Vol. 108(5), pp. 053901 (2016) Charge carriers,Dielectric oxides,Domain walls,Materials properties,Transport properties,area:interfaces,perovskites interfaces Abstract: Density functional theory in combination with the nonequilibrium Green's function formalism is used to study the electronic transport properties of methylammonium lead-iodide perovskite CH3NH3PbI3. Electronic transport in homogeneous ferroelectric and antiferroelectric phases, both of which do not contain any chargeddomain walls, is quite similar. The presence of chargeddomain wall drastically (by about an order of magnitude) enhances the electronic transport in the lateral direction. The increase of the transmission originates from the smaller variation of the electrostatic potential profile along the chargeddomain walls. This fact may provide a tool for tuning transport properties of such hybrid materials by manipulating molecular cations having dipole moment. BibTeX: @article{Berdiyorov2016l, title = {Electronic transport in organometallic perovskite CH3NH3PbI3: The role of organic cation orientations}, author = {Berdiyorov, G. R. and El-Mellouhi, F. and Madjet, M. E. and Alharbi, F. H. and Rashkeev, S. N.}, journal = {Applied Physics Letters}, volume = {108}, number = {5}, pages = {053901}, year = {2016}, keywords = {Charge carriers,Dielectric oxides,Domain walls,Materials properties,Transport properties,area:interfaces,perovskites}, area = {interfaces} doi = {10.1063/1.4941296}, }  Yukihito Matsuura, Electronic transport properties of silicon clusters, Chemical Physics Letters, Vol. 645 pp. 97--99 (2016) area:molecular electronics molecular electronics Abstract: The electronic transport properties of silicon clusters were examined via theoretical calculations using the first-principles method. Additionally, p-type doping and n-type doping were analyzed by calculating conductance and current of boron- and phosphorus-doped silicon clusters. The p-type doping and n-type doping provided a new transmission peak at an energy level around the Fermi level to increase conductance. Furthermore, simultaneous boron and phosphorus doping resulted in noticeable rectifying characteristics, with the current drive in forward bias being three times higher than that in the reverse bias. A p-n junction was achieved even on a molecular scale. BibTeX: @article{Matsuura2016, title = {Electronic transport properties of silicon clusters}, author = {Matsuura, Yukihito}, journal = {Chemical Physics Letters}, publisher = {Elsevier B.V.}, volume = {645}, pages = {97--99}, year = {2016}, keywords = {area:molecular electronics}, area = {molecular electronics} doi = {10.1016/j.cplett.2015.12.040}, }  Yipeng An, Mengjun Zhang, Dapeng Wu, Zhaoming Fu, Tianxing Wang & Congxin Xia, Electronic transport properties of the first all-boron fullerene B 40 and its metallofullerene Sr@B 40, Phys. Chem. Chem. Phys., Vol. 18(17), pp. 12024--12028 (2016) area:fullerenes,boron compounds,transmission pathways fullerenes Abstract: The newly-discovered B40 is the first experimentally observed all-boron fullerene and has potential applications in molecular devices. Herein, we report the electronic transport properties of B40 and its metallofullerene, Sr@B40, using the first-principles technique. We obtain the conductance of B40 fullerene, which is about 130 μS and can be increased by embedding a strontium metal atom in the cage due to the decreased energy gap. Both the current-voltage (I-V) curves of B40 and Sr@B40 present perfect linear characteristics. Intuitively, it is assumed that the electron currents pass through the B40 fullerene mainly along the surface B-B bonds, while two types of new B-Sr-B bond currents and B→Sr→B hopping currents are presented for Sr@B40 due to Sr acting as a bridge. This study provides valuable information for the potential applications of future borospherene-based molecular devices. BibTeX: @article{An2016a, title = {Electronic transport properties of the first all-boron fullerene B 40 and its metallofullerene Sr@B 40}, author = {An, Yipeng and Zhang, Mengjun and Wu, Dapeng and Fu, Zhaoming and Wang, Tianxing and Xia, Congxin}, journal = {Phys. Chem. Chem. Phys.}, publisher = {Royal Society of Chemistry}, volume = {18}, number = {17}, pages = {12024--12028}, year = {2016}, keywords = {area:fullerenes,boron compounds,transmission pathways}, area = {fullerenes} doi = {10.1039/C6CP01096B}, }  Tue Gunst, Troels Markussen, Kurt Stokbro & Mads Brandbyge, First-principles method for electron-phonon coupling and electron mobility: Applications to two-dimensional materials, Physical Review B - Condensed Matter and Materials Physics, Vol. 93 pp. 035414 (2016) MoS2,QWpaper,area:2dmat,area:graphene,electron-phonon 2dmat,graphene Abstract: We present density functional theory calculations of the phonon-limited mobility in n-type monolayer graphene, silicene and MoS$2$. The material properties, including the electron-phonon interaction, are calculated from first-principles. We provide a detailed description of the normalized full-band relaxation time approximation for the linearized Boltzmann transport equation (BTE) that includes inelastic scattering processes. The bulk electron-phonon coupling is evaluated by a supercell method. The method employed is fully numerical and does therefore not require a semi-analytic treatment of part of the problem and, importantly, it keeps the anisotropy information stored in the coupling as well as the band structure. In addition, we perform calculations of the low-field mobility and its dependence on carrier density and temperature to obtain a better understanding of transport in graphene, silicene and monolayer MoS$2$. Unlike graphene, the carriers in silicene show strong interaction with the out-of-plane modes. We find that graphene has more than an order of magnitude higher mobility compared to silicene. For MoS$2$, we obtain several orders of magnitude lower mobilities in agreement with other recent theoretical results. The simulations illustrate the predictive capabilities of the newly implemented BTE solver applied in simulation tools based on first-principles and localized basis sets. BibTeX: @article{Gunst2016a, title = {First-principles method for electron-phonon coupling and electron mobility: Applications to two-dimensional materials}, author = {Gunst, Tue and Markussen, Troels and Stokbro, Kurt and Brandbyge, Mads}, journal = {Physical Review B - Condensed Matter and Materials Physics}, volume = {93}, pages = {035414}, year = {2016}, keywords = {MoS2,QWpaper,area:2dmat,area:graphene,electron-phonon}, area = {2dmat,graphene} doi = {10.1103/PhysRevB.93.035414}, }  Golibjon R. Berdiyorov & Mohamed El-Amine Madjet, First-principles study of electronic transport and optical properties of penta-graphene, penta-SiC 2 and penta-CN 2, RSC Adv., Vol. 6(56), pp. 50867--50873 (2016) area:2dmat,penta-graphene 2dmat Abstract: Using density functional theory in combination with the nonequilibrium Green's function formalism we study the electronic transport properties, optical properties and atomic partial charges of the recently proposed isostructural materials: penta-graphene (PG), pentagonal silicon dicarbide (p-SiC2) and pentagonal carbon nitride (p-CN2). Enhanced electronic transport is obtained in p-SiC2 as compared to PG due to the delocalization of the electronic states and smaller variations of the electrostatic potential. This enhancement occurs despite a smaller contribution of Si atoms to the density of states of the system. Penta-SiC2 also displays improved dielectric and optical properties as compared to its all-carbon analogue. For example, larger absorption is obtained in both the visible and the ultraviolet spectral ranges. Strong variation in the atomic partial charge distribution was found in p-SiC2. On the contrary, p-CN2 was not found to exhibit improved optoelectronic properties compared to PG, except for larger partial charges on the surface of the sample. Our findings demonstrate the potential of p-SiC2 in optoelectronic applications. BibTeX: @article{Berdiyorov2016i, title = {First-principles study of electronic transport and optical properties of penta-graphene, penta-SiC 2 and penta-CN 2}, author = {Berdiyorov, Golibjon R. and Madjet, Mohamed El-Amine}, journal = {RSC Adv.}, publisher = {Royal Society of Chemistry}, volume = {6}, number = {56}, pages = {50867--50873}, year = {2016}, keywords = {area:2dmat,penta-graphene}, area = {2dmat} doi = {10.1039/C6RA10376F}, }  Sudhanshu Choudhary, Pradeep Mishra & Rohit Goyal, First-principles study of spin transport in BN doped CrO2–graphene–CrO2 magnetic tunnel junction, Physics Letters A, Vol. 380(9-10), pp. 1098--1101 (2016) Boron–Nitrogen doping,Graphene nanosheet,Half-metallic–ferromagnetic (HMF) electrodes,Magnetic tunnel junction (MTJ),Spin efficiency,Tunnel magnetoresistance (TMR),area:graphene,area:spintronics graphene,spintronics Abstract: We investigate the spin-dependent electronic transport properties of Magnetic tunnel junction (MTJ) consisting of Boron (B) and Nitrogen (N) doped graphene nanosheet sandwiched between two CrO2 half-metallic–ferromagnet (HMF) electrodes. A large value of tunnel magnetoresistance (TMR) and perfect spin filtration was obtained as compared to un-doped graphene MTJ structures reported in past. The use of HMF electrodes further raises the TMR and improves the spin filtration in comparison to MTJs with metallic and ferromagnetic (FM) electrodes, which suggest HMF electrodes as a suitable candidate over metallic and FM electrodes for implementing graphene sheet based MTJs. A high value of TMR ∼100% is obtained at zero bias voltage, which remains constantly high at higher bias voltages in the range of 0 V to 1 V. The higher value of TMR and better (near perfect) spin filtration abilities suggest its usefulness in spin-valves and other spintronics based applications. The spin-dependent non-equilibrium transport is also investigated by analyzing the bias dependent transmission coefficients. BibTeX: @article{Choudhary2016, title = {First-principles study of spin transport in BN doped CrO2–graphene–CrO2 magnetic tunnel junction}, author = {Choudhary, Sudhanshu and Mishra, Pradeep and Goyal, Rohit}, journal = {Physics Letters A}, publisher = {Elsevier B.V.}, volume = {380}, number = {9-10}, pages = {1098--1101}, year = {2016}, keywords = {Boron–Nitrogen doping,Graphene nanosheet,Half-metallic–ferromagnetic (HMF) electrodes,Magnetic tunnel junction (MTJ),Spin efficiency,Tunnel magnetoresistance (TMR),area:graphene,area:spintronics}, area = {graphene,spintronics} doi = {10.1007/s10825-015-0725-x}, }  Daniele Stradi, Umberto Martinez, Anders Blom, Mads Brandbyge & Kurt Stokbro, General atomistic approach for modeling metal-semiconductor interfaces using density functional theory and nonequilibrium Green's function, Physical Review B - Condensed Matter and Materials Physics, Vol. 93 pp. 155302 (2016) QWpaper,area,area:semi,metal-semiconductor contact,silicon area,semi Abstract: Metal-semiconductor contacts are a pillar of modern semiconductor technology. Historically, their microscopic understanding has been hampered by the inability of traditional analytical and numerical methods to fully capture the complex physics governing their operating principles. Here we introduce an atomistic approach based on density functional theory and non-equilibrium Green's function, which includes all the relevant ingredients required to model realistic metal-semiconductor interfaces and allows for a direct comparison between theory and experiments via I-V bias curves simulations. We apply this method to characterize an Ag/Si interface relevant for photovoltaic applications and study the rectifying-to-Ohmic transition as function of the semiconductor doping.We also demonstrate that the standard "Activation Energy" method for the analysis of I-V bias data might be inaccurate for non-ideal interfaces as it neglects electron tunneling, and that finite-size atomistic models have problems in describing these interfaces in the presence of doping, due to a poor representation of space-charge effects. Conversely, the present method deals effectively with both issues, thus representing a valid alternative to conventional procedures for the accurate characterization of metal-semiconductor interfaces. BibTeX: @article{Stradi2016, title = {General atomistic approach for modeling metal-semiconductor interfaces using density functional theory and nonequilibrium Green's function}, author = {Stradi, Daniele and Martinez, Umberto and Blom, Anders and Brandbyge, Mads and Stokbro, Kurt}, journal = {Physical Review B - Condensed Matter and Materials Physics}, volume = {93}, pages = {155302}, year = {2016}, keywords = {QWpaper,area,area:semi,metal-semiconductor contact,silicon}, area = {area,semi} doi = {10.1103/PhysRevB.93.155302}, }  Jing Zeng, Fang Xie & Ke-Qiu Chen, High-efficiency spin-filtering and magnetoresistance effects in supramolecular spin valves, Carbon, Vol. 98 pp. 607--612 (2016) BEHAVIORS,CONDUCTANCE,DIODE,ELECTRODES,SPINTRONIC DEVICES,TRANSPORT,area:graphene,area:spintronics,magnetoresistive effect,spin- fi ltering effect,supramolecular spin valve graphene,spintronics Abstract: By using nonequilibrium Green's functions in combination with the density functional theory, we investigate the transport properties of the supramolecular spin valves made of ferrocene and pristine (p-type or n-type) graphene nanoribbons. The results show that ferrocene adsorption on pristine graphene nanoribbons gives rise to perfect magnetoresistive effect. While for ferrocene adsorption on p-type graphene nanoribbons, the perfect magnetoresistive effect disappears but a high-efficiency spin-filtering effect can be observed. More interestingly, the ferrocene adsorption on n-type graphene nanoribbons bring about the disappearance of spin polarization effect, and thus spin-filtering and magnetoresistive effect cannot be observed. Our researches also confirm that the doping type of graphene nanoribbons is a key factor for obtaining a high-performance supramolecular spintronic device. BibTeX: @article{Zeng2016, title = {High-efficiency spin-filtering and magnetoresistance effects in supramolecular spin valves}, author = {Zeng, Jing and Xie, Fang and Chen, Ke-Qiu}, journal = {Carbon}, volume = {98}, pages = {607--612}, year = {2016}, keywords = {BEHAVIORS,CONDUCTANCE,DIODE,ELECTRODES,SPINTRONIC DEVICES,TRANSPORT,area:graphene,area:spintronics,magnetoresistive effect,spin- fi ltering effect,supramolecular spin valve}, area = {graphene,spintronics} doi = {10.1016/j.carbon.2015.11.046}, }  Anurag Srivastava, B. Santhibhushan, Vikash Sharma, Kamalpreet Kaur, Md Shahzad Khan, Madura Marathe, Abir De Sarkar & Mohd Shahid Khan, Influence of Boron Substitution on Conductance of Pyridine- and Pentane-Based Molecular Single Electron Transistors: First-Principles Analysis, Journal of Electronic Materials, Vol. 45(4), pp. 2233--2241 (2016) (C4H12B),1,2-azaborine (C4H5NB),Density functional theory (DFT),area:molecular electronics,boron (B),butylborane,charge stability diagram,natural bond orbital (NBO),single-electron,threshold voltage (Vth),transistor (SET) molecular electronics Abstract: We have investigated the modeling of boron-substituted molecular single-electron transistor (SET), under the influence of a weak coupling regime of Coulomb blockade between source and drain metal electrodes. The SET consists of a single organic molecule (pyridine/pentane/1,2-azaborine/butylborane) placed over the dielectric, with boron (B) as a substituent. The impact of B-substitution on pyridine and pentane molecules in isolated, as well as SET, environments has been analyzed by using density functional theory-based ab initio packages Atomistix toolkit-Virtual NanoLab and Gaussian03. The performance of proposed SETs was analyzed through charging energies, total energy as a function of gate potential and charge stability diagrams. The analysis confirms that the B-substituted pentane (butylborane) and the boron-substituted pyridine (1,2-azaborine) show remarkably improved conductance in SET environment in comparison to simple pyridine and pentane molecules. BibTeX: @article{Srivastava2016, title = {Influence of Boron Substitution on Conductance of Pyridine- and Pentane-Based Molecular Single Electron Transistors: First-Principles Analysis}, author = {Srivastava, Anurag and Santhibhushan, B. and Sharma, Vikash and Kaur, Kamalpreet and Shahzad Khan, Md and Marathe, Madura and De Sarkar, Abir and Shahid Khan, Mohd}, journal = {Journal of Electronic Materials}, volume = {45}, number = {4}, pages = {2233--2241}, year = {2016}, keywords = {(C4H12B),1,2-azaborine (C4H5NB),Density functional theory (DFT),area:molecular electronics,boron (B),butylborane,charge stability diagram,natural bond orbital (NBO),single-electron,threshold voltage (Vth),transistor (SET)}, area = {molecular electronics} doi = {10.1007/s11664-015-4287-2}, }  Hari Mohan Rai, Shailendra K. Saxena, Vikash Mishra, Ravikiran Late, Rajesh Kumar, Pankaj R. Sagdeo, Neeraj K. Jaiswal & Pankaj Srivastava, Intrinsic Half-metallicity in Edge Fluorinated Armchair Boron Nitride Nanoribbons, RSC Advances, Vol. 6 pp. 11014--11022 (2016) Boron nitride,area:2dmat,area:materials,area:spintronics,fluorination,molecules,nanoribbon 2dmat,materials,spintronics Abstract: We predict intrinsic half-metallicity in armchair boron nitride nanoribbons (ABNNRs) via edge fluorination. The stability, electronic and magnetic properties of bare and edge fluorinated ABNNRs have been systematically analyzed by means of first-principles calculations within the local spin-density approximation (LSDA). The ribbons whose only edge-B atoms passivated with F atoms (i.e., edge-N atoms are un-passivated), regardless of width, are found half-metallic with a half-metal gap of 0.3 eV. A 100 % spin polarized charge transport across the Fermi level is expected for such ribbons as the spin polarized states are ∼0.4 eV more stable than the spin un-polarized states and only single-spin conducting channels are present across the Fermi level owing to the gigantic spin splitting. The existence of half-metallicity is attributed to the localization of electronic charge at bare edge-N atoms as revealed from the analysis of Bloch states and projected density of states (PDOS).The sufficiently large half-metal gap (0.3 eV) with huge difference in the energies (∼ 0.4 eV) of spin polarized and spin compensated states projects these half-metallic ABNNRs as potential candidate for spintronics applications. BibTeX: @article{Rai2015b, title = {Intrinsic Half-metallicity in Edge Fluorinated Armchair Boron Nitride Nanoribbons}, author = {Rai, Hari Mohan and Saxena, Shailendra K and Mishra, Vikash and Late, Ravikiran and Kumar, Rajesh and Sagdeo, Pankaj R and Jaiswal, Neeraj K and Srivastava, Pankaj}, journal = {RSC Advances}, volume = {6}, pages = {11014--11022}, year = {2016}, keywords = {Boron nitride,area:2dmat,area:materials,area:spintronics,fluorination,molecules,nanoribbon}, area = {2dmat,materials,spintronics} doi = {10.1039/C5RA21832B}, }  M. Deekshitha, Anurag Srivastava & R. Chandiramouli, Investigation on transport property of In2O3 molecular device — A first-principles study, Microelectronic Engineering, Vol. 151 pp. 1--6 (2016) Band structure,Density of states,Electron density,Indium oxide,Molecular device,area:interfaces interfaces Abstract: The band structures and the electronic transport properties of In2O3 molecular device are studied with GGA/PBE exchange correlation functional using the Density Functional Theory (DFT). The band structure of In2O3 nanostructure exhibits the semiconducting behavior. The electron density is less in the indium sites than in the oxygen sites. The localization of charges is envisioned using density of states spectrum. The device density of states of In2O3 molecular device infers that the density of charges can be fine-tuned by increasing the bias voltage in the energy intervals. The transmission spectrum is used to study the transport properties of In2O3 molecular device. The possible transmission paths along In2O3 scattering region are visualized using transmission pathways. The finding of the present work gives the insight on In2O3 molecular device, which can be used as chemical sensors in the detection of toxic gases. BibTeX: @article{Deekshitha2016, title = {Investigation on transport property of In2O3 molecular device — A first-principles study}, author = {Deekshitha, M. and Srivastava, Anurag and Chandiramouli, R.}, journal = {Microelectronic Engineering}, publisher = {Elsevier B.V.}, volume = {151}, pages = {1--6}, year = {2016}, keywords = {Band structure,Density of states,Electron density,Indium oxide,Molecular device,area:interfaces}, area = {interfaces} doi = {10.1016/j.mee.2015.11.010}, }  Golibjon R. Berdiyorov, Mohamed E. Madjet & Khaled A. Mahmoud, Ionic sieving through Ti3C2(OH)2 MXene: First-principles calculations, Applied Physics Letters, Vol. 108(11), pp. 113110 (2016) Density functional theory,Double layers,Electrostatics,MXenes,Sodium,Surface charge,area:interfaces,area:materials interfaces,materials Abstract: Recent experiments revealed a great potential of MXene nanosheets for water desalination applications as ultrathin, high-flux, and size/charge-selective sieving membranes. Here, we conduct first-principles density functional theory calculations to explore possible mechanisms for the charge-selective ionic transport through Ti3C2(OH)2 MXene. We find that the charge selectivity originates from the charged nature of the MXene layers. For example, due to the electrostatic interactions, ions of different charge states have different energy barriers for the intercalation between the MXene layers. In addition, the system shows dynamic response to the intercalating ions, even in their hydrated states, by changing the interlayer spacing. Our findings highlight the importance of membranesurfacecharges on the ion sieving performance. BibTeX: @article{Berdiyorov2016k, title = {Ionic sieving through Ti3C2(OH)2 MXene: First-principles calculations}, author = {Berdiyorov, Golibjon R. and Madjet, Mohamed E. and Mahmoud, Khaled A.}, journal = {Applied Physics Letters}, volume = {108}, number = {11}, pages = {113110}, year = {2016}, keywords = {Density functional theory,Double layers,Electrostatics,MXenes,Sodium,Surface charge,area:interfaces,area:materials}, area = {interfaces,materials} doi = {10.1063/1.4944393}, }  Jie Jiang, Ruth Pachter, Teresa Demeritte, Paresh C. Ray, Ahmad E. Islam, Benji Maruyama & John J. Boeckl, Modeling Graphene with Nanoholes: Structure and Characterization by Raman Spectroscopy with Consideration for Electron Transport, Journal of Physical Chemistry C, Vol. 120(10), pp. 5371--5383 (2016) area:graphene,graphene oxide graphene Abstract: Recent advances in controlled synthesis and characterization of single-layer graphene nanostructures with defects provide the basis for gaining an understanding of the complex nanomaterials by theoretical investigation. In this work, we modeled defective single-layer graphene (DSLG), where nanostructures with divacancy, trivacancy, tetravacancy, pentavacancy, hexavacancy, and heptavacancy defects, having pore sizes from 0.1 to 0.5 nm, were considered. Nanostructures with molecular oxygen adsorption to mimic experimental conditions were also investigated. On the basis of calculated formation energies of the optimized nanostructures, a few DSLGs were selected for theoretical characterization of the defect-induced I(D)/I(D′) Raman intensity ratios. We found that the I(D)/I(D′) ratio decreases with an increase in the nanohole size and in the number of adsorbed oxygens, which explains an experimental observation of a decrease in this characterization signature with an increase in exposure time to oxygen plasma. The predicted ratio was also confirmed by Raman spectroscopy measurements for graphene oxide quantum dots. The results were rationalized based on an analytical analysis of the D′ band electron-defect matrix elements. Finally, consideration of patterned graphene nanostructures with vacancies for field effect transistor (FET) application was shown to provide a route to bandgap generation, and potentially improvement of the Ion/Ioff ratio in a FET by nanohole passivation, e.g., by hydrogenation. FETs based on patterned graphene with small pores could have a similar high level of performance as graphene nanoribbons, however with the added benefit of no width confinement. BibTeX: @article{Jiang2016b, title = {Modeling Graphene with Nanoholes: Structure and Characterization by Raman Spectroscopy with Consideration for Electron Transport}, author = {Jiang, Jie and Pachter, Ruth and Demeritte, Teresa and Ray, Paresh C. and Islam, Ahmad E. and Maruyama, Benji and Boeckl, John J.}, journal = {Journal of Physical Chemistry C}, volume = {120}, number = {10}, pages = {5371--5383}, year = {2016}, keywords = {area:graphene,graphene oxide}, area = {graphene} doi = {10.1021/acs.jpcc.5b10225}, }  A. Arab, A.V. Davydov, D.A. Papaconstantopoulos & Q. Li, Monolayer MoS2 Nanoribbons as a Promising Material for Both n-type and p-type Legs in Thermoelectric Generators, Journal of Electronic Materials, Vol. 45(10), pp. 5253--5263 (2016) MoS2 Nanoribbon,Thermoelectric generation,ZT,area:2dmat,area:tmd,seebeck coefficient 2dmat,tmd Abstract: First-principles calculations have been performed to study the thermoelectric properties of monolayer MoS2 armchair nanoribbons (ACNRs). The electronic behavior of nanoribbons is dominated by the presence of edge states that are dependent on the number of zigzag chains across the nanoribbon. In addition, it is found that the phonon thermal conductance of monolayer MoS2 ACNRs is smaller than monolayer films due to phonon edge scattering. This effect is more pronounced in narrower nanoribbons, which leads to a higher ZT value compared to a monolayer MoS2 sheet. The effects of sulfur vacancy and edge roughness on the thermoelectric properties of MoS2 ACNRs have also been studied. We found that edge roughness decreased ZT values compared to those of perfect nanoribbons, as its impact on electrical conductance is more severe than on phonon thermal conductance. Sulfur vacancy, however, improved ZT in some subbands. It is shown that ZT values as high as 4 for electron-doped and 3 for hole-doped nanoribbons can be achieved at T = 500 K. The ability to achieve high ZT values for both p-type and n-type nanoribbons makes monolayer MoS2 ACNR a promising candidate for future solid-state thermoelectric generators. BibTeX: @article{Arab2016, title = {Monolayer MoS2 Nanoribbons as a Promising Material for Both n-type and p-type Legs in Thermoelectric Generators}, author = {Arab, A. and Davydov, A. V. and Papaconstantopoulos, D. A. and Li, Q.}, journal = {Journal of Electronic Materials}, volume = {45}, number = {10}, pages = {5253--5263}, year = {2016}, keywords = {MoS2 Nanoribbon,Thermoelectric generation,ZT,area:2dmat,area:tmd,seebeck coefficient}, area = {2dmat,tmd} doi = {10.1007/s11664-016-4725-9}, }  Feras Al-Dirini, Faruque M. Hossain, Mahmood A. Mohammed, Md Sharafat Hossain, Ampalavanapillai Nirmalathas & Efstratios Skafidas, Monolayer MoS2 self-switching diodes, Journal of Applied Physics, Vol. 119(4), pp. 044506 (2016) Band gap,Diodes,Doping,Field-effect transistors,Graphene,Nano-structures,Rectification,Tunnel-effect diodes,Tunneling,area:2dmat,area:tmd 2dmat,tmd Abstract: This paper presents a new molybdenum disulphide (MoS2) nanodevice that acts as a two-terminal field-effect rectifier. The device is an atomically-thin two-dimensional self-switching diode (SSD) that can be realized within a single MoS2monolayer with very minimal process steps. Quantum simulation results are presented confirming the device's operation as a diode and showing strong non-linear I-V characteristics. Interestingly, the device shows p-type behavior, in which conduction is dominated by holes as majority charge carriers and the flow of reverse current is enhanced, while the flow of forward current is suppressed, in contrast to monolayergraphene SSDs, which behave as n-type devices. The presence of a large bandgap in monolayer MoS2 results in strong control over the channel, showing complete channel pinch-off in forward conduction, which was confirmed with transmission pathways plots. The device exhibited large leakage tunnelling current through the insulating trenches, which may have been due to the lack of passivation; nevertheless, reverse current remained to be 6 times higher than forward current, showing strong rectification. The effect of p-type substitutional channel doping of sulphur with phosphorus was investigated and showed that it greatly enhances the performance of the device, increasing the reverse-to-forward current rectification ratio more than an order of magnitude, up to a value of 70. BibTeX: @article{Al-Dirini2016b, title = {Monolayer MoS2 self-switching diodes}, author = {Al-Dirini, Feras and Hossain, Faruque M. and Mohammed, Mahmood A. and Hossain, Md Sharafat and Nirmalathas, Ampalavanapillai and Skafidas, Efstratios}, journal = {Journal of Applied Physics}, volume = {119}, number = {4}, pages = {044506}, year = {2016}, keywords = {Band gap,Diodes,Doping,Field-effect transistors,Graphene,Nano-structures,Rectification,Tunnel-effect diodes,Tunneling,area:2dmat,area:tmd}, area = {2dmat,tmd} doi = {10.1063/1.4940707}, }  Yuanyuan Pan, Yangyang Wang, Meng Ye, Ruge Quhe, Hongxia Zhong, Zhigang Song, Xiyou Peng, Dapeng Yu, Jinbo Yang, Junjie Shi & Jing Lu, Monolayer Phosphorene-Metal Contacts, Chemistry of Materials, Vol. 28(7), pp. 2100--2109 (2016) Computational Physics,Materials Science,Mesoscale and Nanoscale Physics,area:2dmat,area:materials 2dmat,materials Abstract: Recently, phosphorene electronic and optoelectronic prototype devices have been fabricated with various metal electrodes. We systematically explore for the first time the contact properties of monolayer (ML) phosphorene with a series of commonly used metals in a transistor by using both ab initio electronic structure calculations and more reliable quantum transport simulations. ML phosphorene undergoes a metallization under the checked metals, and the metallized ML phosphorenes have an unnegligible coupling with channel ML phosphorene. ML phosphorene forms an n-type Schottky contact with Au, Cu, Cr, Al, and Ag electrodes and a p-type Schottky contact with Ti, Ni, and Pd electrodes upon inclusion of such a coupling. The calculated Schottky barrier heights are in good agreement with the available experimental data with Ni and Ti as electrodes. Our findings not only provide an insight into the ML phosphorene?metal interfaces but also help in ML phosphorene based device design. BibTeX: @article{Pan2016, title = {Monolayer Phosphorene-Metal Contacts}, author = {Pan, Yuanyuan and Wang, Yangyang and Ye, Meng and Quhe, Ruge and Zhong, Hongxia and Song, Zhigang and Peng, Xiyou and Yu, Dapeng and Yang, Jinbo and Shi, Junjie and Lu, Jing}, journal = {Chemistry of Materials}, volume = {28}, number = {7}, pages = {2100--2109}, year = {2016}, keywords = {Computational Physics,Materials Science,Mesoscale and Nanoscale Physics,area:2dmat,area:materials}, area = {2dmat,materials} doi = {10.1021/acs.chemmater.5b04899}, }  Yuhong Zhou, Nianxiang Qiu, Runwei Li, Zhansheng Guo, Jian Zhang, Junfeng Fang, Aisheng Huang, Jian He, Xianhu Zha, Kan Luo, Jingshuo Yin, Qiuwu Li, Xiaojing Bai, Qing Huang & Shiyu Du, Negative differential resistance and rectifying performance induced by doped graphene nanoribbons p-n device, Physics Letters, Section A: General, Atomic and Solid State Physics, Vol. 380(9-10), pp. 1049--1055 (2016) Electronic transport properties,First-principles,Graphene nanoribbons,Negative differential resistance,Rectifying performance,area:graphene,area:semi graphene,semi Abstract: Employing nonequilibrium Green's Functions in combination with density functional theory, the electronic transport properties of armchair graphene nanoribbon (GNR) devices with various widths are investigated in this work. In the adopted model, two semi-infinite graphene electrodes are periodically doped with boron or nitrogen atoms. Our calculations reveal that these devices have a striking nonlinear feature and show notable negative differential resistance (NDR). The results also indicate the diode-like properties are reserved and the rectification ratios are high. It is found the electronic transport properties are strongly dependent on the width of doped nanoribbons and the positions of dopants and three distinct families are elucidated for the current armchair GNR devices. The NDR as well as rectifying properties can be well explained by the variation of transmission spectra and the relative shift of discrete energy states with applied bias voltage. These findings suggest that the doped armchair GNR is a promising candidate for the next generation nanoscale device. BibTeX: @article{Zhou2016, title = {Negative differential resistance and rectifying performance induced by doped graphene nanoribbons p-n device}, author = {Zhou, Yuhong and Qiu, Nianxiang and Li, Runwei and Guo, Zhansheng and Zhang, Jian and Fang, Junfeng and Huang, Aisheng and He, Jian and Zha, Xianhu and Luo, Kan and Yin, Jingshuo and Li, Qiuwu and Bai, Xiaojing and Huang, Qing and Du, Shiyu}, journal = {Physics Letters, Section A: General, Atomic and Solid State Physics}, publisher = {Elsevier B.V.}, volume = {380}, number = {9-10}, pages = {1049--1055}, year = {2016}, keywords = {Electronic transport properties,First-principles,Graphene nanoribbons,Negative differential resistance,Rectifying performance,area:graphene,area:semi}, area = {graphene,semi} doi = {10.1016/j.physleta.2016.01.010}, }  Liming Jiang, Wanzhi Qiu, Md Sharafat Hossain, Feras Al-Dirini, Robin Evans & Efstratios Skafidas, Non-equilibrium tunneling in zigzag graphene nanoribbon break-junction results in spin filtering, Journal of Applied Physics, Vol. 119(5), pp. 053902 (2016) Electrodes,Graphene,Spintronic devices,Transmission coefficient,Tunneling,area:graphene,area:spin graphene,spin Abstract: Spintronic devices promise new faster and lower energy-consumption electronic systems. Graphene, a versatile material and candidate for next generation electronics, is known to possess interesting spintronicproperties. In this paper, by utilizing density functional theory and non-equilibrium green function formalism, we show that Fano resonance can be generated by introducing a break junction in a zigzag graphene nanoribbon (ZGNR). Using this effect, we propose a new spin filtering device that can be used for spin injection. Our theoretical results indicate that the proposed device could achieve high spin filtering efficiency (over 90%) at practical fabrication geometries. Furthermore, our results indicate that the ZGNR break junction lattice configuration can dramatically affect spin filtering efficiency and thus needs to be considered when fabricating real devices. Our device can be fabricated on top of spin transport channel and provides good integration between spin injection and spin transport. BibTeX: @article{Jiang2016d, title = {Non-equilibrium tunneling in zigzag graphene nanoribbon break-junction results in spin filtering}, author = {Jiang, Liming and Qiu, Wanzhi and Sharafat Hossain, Md and Al-Dirini, Feras and Evans, Robin and Skafidas, Efstratios}, journal = {Journal of Applied Physics}, volume = {119}, number = {5}, pages = {053902}, year = {2016}, keywords = {Electrodes,Graphene,Spintronic devices,Transmission coefficient,Tunneling,area:graphene,area:spin}, area = {graphene,spin} doi = {10.1063/1.4940018}, }  G.R. Berdiyorov, Optical properties of functionalized Ti3C2T2 (T = F, O, OH) MXene: First-principles calculations, AIP Advances, Vol. 6(5), pp. 055105 (2016) Absorption spectra,MXenes,Materials properties,Optical properties,Photons,Reflectivity,area:2dmat,grimme 2dmat Abstract: Role of surface termination on the dielectric and optical properties of Ti3C2T2 (T = F, O, OH) MXene is studied using first-principles density functional theory. The results show that the surface functionalization has a significant impact on the optical properties of the MXene. For example, in the visible range of the spectrum, the oxidized sample shows larger absorption, whereas surface fluorination results in weaker absorption as compared to pristine MXene. In the ultraviolet energy range, all functional groups lead to the enhancement of both absorption and reflectivity of the material. Dielectric properties of MXene are also sensitive to the surface functionalization. Our findings demonstrate the importance of surface termination on the optical properties of the MXene. BibTeX: @article{Berdiyorov2016j, title = {Optical properties of functionalized Ti3C2T2 (T = F, O, OH) MXene: First-principles calculations}, author = {Berdiyorov, G. R.}, journal = {AIP Advances}, volume = {6}, number = {5}, pages = {055105}, year = {2016}, keywords = {Absorption spectra,MXenes,Materials properties,Optical properties,Photons,Reflectivity,area:2dmat,grimme}, area = {2dmat} doi = {10.1063/1.4948799}, }  L. Banerjee, A. Mukhopadhyay, A. Sengupta & H. Rahaman, Performance analysis of uniaxially strained monolayer black phosphorus and blue phosphorus n-MOSFET and p-MOSFET, Journal of Computational Electronics, Vol. 15(3), pp. 919--930 (2016) Black phosphorus,Blue phosphorus,Density functional theory (DFT),MOSFET,Nonequilibrium Green's function (NEGF),Strain,area:2dmat 2dmat Abstract: In this work, we present a comput ational study on the possibility of strain engineering in monolayer Black Phosphorus (black P) and Blue Phosph orus (blue P) based MOSFETs. The material properties like band structure, carrier effective masses, carrier densities at band extrema are evaluated using Generalized Gradient Approximation (GGA) in Density Functional Theory (DFT). Thereafter self-consistent Non-Equilibrium Green's Function (NEGF) simulations are carried out to study the device performance metrics (such as output characteristics, ON currents, transconductance etc.) of such strained blac k P and blue P based MOSFETs. Our simulations show that carrier effective masses in blue P are more sensitive to strain applied in both zigzag and armchair directions. Blue P is more responsive in strain engineering for n-MOS and p-MOS. Except for black P based FETs with strain in armc hair direction, overall the blue P (black P) n- MOSFET (p-MOSFET) show moderate to signific ant improvement in performance with tensile (compressive) strain in the transport directions BibTeX: @article{Banerjee2016, title = {Performance analysis of uniaxially strained monolayer black phosphorus and blue phosphorus n-MOSFET and p-MOSFET}, author = {Banerjee, L. and Mukhopadhyay, A. and Sengupta, A. and Rahaman, H.}, journal = {Journal of Computational Electronics}, volume = {15}, number = {3}, pages = {919--930}, year = {2016}, keywords = {Black phosphorus,Blue phosphorus,Density functional theory (DFT),MOSFET,Nonequilibrium Green's function (NEGF),Strain,area:2dmat}, area = {2dmat} doi = {10.1007/s10825-016-0846-x}, }  Hari Mohan Rai, Shailendra K. Saxena, Vikash Mishra, Ravikiran Late, Rajesh Kumar, Pankaj R. Sagdeo, Neeraj K. Jaiswal & Pankaj Srivastava, Possibility of spin-polarized transport in edge fluorinated armchair boron nitride nanoribbons, RSC Adv., Vol. 6(13), pp. 11014--11022 (2016) area:2dmat,area:spin,boron nitride,nanoribbons 2dmat,spin Abstract: We predict the possibility of spin based electronic transport in edge fluorinated armchair boron nitride nanoribbons (ABNNRs). The structural stability, electronic and magnetic properties of these edge fluorinated ABNNRs have been systematically analyzed by means of first-principles calculations within the local spin-density approximation (LSDA). Regardless of their width, ABNNRs with F-passivation at only the edge-B atoms are found to be thermodynamically stable and half-metallic in nature. The spin polarized states are found to be ∼0.4 eV more stable than that of spin compensated states. Further, upto 100% spin polarization is expected in ABNNRs with F-passivation at only the edge-B atoms as indicated by the giant splitting of spin states which is observed in the corresponding band structures, DOS and transmission spectrum. The existence of half-metallicity is attributed to the localization of electronic charge at unpassivated edge-N atoms as revealed from the analysis of Bloch states and projected density of states (PDOS). Importantly, present stability analysis suggests that the possibility of experimental realization of spin polarized transport in ABNNRs is more promising via F-passivation of ribbon edges than that of H-passivation. The observed half-metallic nature and large difference in the energies (∼0.4 eV) of spin polarized and spin compensated states projects these half-metallic ABNNRs as potential candidates for inorganic spintronic applications. BibTeX: @article{Rai2016, title = {Possibility of spin-polarized transport in edge fluorinated armchair boron nitride nanoribbons}, author = {Rai, Hari Mohan and Saxena, Shailendra K. and Mishra, Vikash and Late, Ravikiran and Kumar, Rajesh and Sagdeo, Pankaj R. and Jaiswal, Neeraj K. and Srivastava, Pankaj}, journal = {RSC Adv.}, publisher = {Royal Society of Chemistry}, volume = {6}, number = {13}, pages = {11014--11022}, year = {2016}, keywords = {area:2dmat,area:spin,boron nitride,nanoribbons}, area = {2dmat,spin} doi = {10.1039/C5RA21832B}, }  Oliver Böhm, Stephan Pfadenhauer, Roman Leitsmann, Philipp Plänitz, Eduard Schreiner & Michael Schreiber, ReaxFF + -A New Reactive Force Field Method for the Accurate Description of Ionic Systems and Its Application to the Hydrolyzation of Aluminosilicates, The Journal of Physical Chemistry C, Vol. 120(20), pp. 10849--10856 (2016) area:materials,atkclassical,reaxff materials Abstract: In this paper we present a powerful extension of the reactive force field method ReaxFF, which we call ReaxFF+. It combines the charge equilibrium scheme with the bond order principle. The main advantage of this procedure is the correct distinction and description of covalent and ionic bonds. It allows reactive molecular dynamic simulations in ionic gases and liquids. To demonstrate the accuracy of this new method, we study the hydrolyzation of aluminosilicates. Comparing the results with experimental and ab initio data, we can prove the high accuracy of our method. This shows that ReaxFF+ is a powerful force field simulation tool for reactions in acidic or alkaline environments. BibTeX: @article{Bohm2016, title = {ReaxFF + -A New Reactive Force Field Method for the Accurate Description of Ionic Systems and Its Application to the Hydrolyzation of Aluminosilicates}, author = {Böhm, Oliver and Pfadenhauer, Stephan and Leitsmann, Roman and Plänitz, Philipp and Schreiner, Eduard and Schreiber, Michael}, journal = {The Journal of Physical Chemistry C}, volume = {120}, number = {20}, pages = {10849--10856}, year = {2016}, keywords = {area:materials,atkclassical,reaxff}, area = {materials} doi = {10.1021/acs.jpcc.6b00720}, }  Yipeng An, Mengjun Zhang, Tianxing Wang, Guangtao Wang & Zhaoming Fu, Rectifications in organic single-molecule diodes alkanethiolate-terminated heterocyclics, Vol. 380(7-8), pp. 923--926 (2016) Charge transport,First-principles calculation,Molecular device,Nanoscale electronics,Non-equilibrium Green's function,Rectifier,area:molecular electronics molecular electronics Abstract: Based on the non-equilibrium Green's function formalism combined with the ab initio density functional theory, we investigate the rectifying behaviors of the organic single-molecule S(CH2)11-terminated with a variety of heterocyclics (i.e., BIPY, PHE, PHEPY, and PYR) coupled with two semi-infinite Au electrodes. Our quantum transport calculation results show that the BIPY and PHE nanojunctions show the high-efficiency rectifying effects. While, differently, the current-voltage (I-V) curves of PHEPY and PYR nanojunctions display the insulating and linear characters, respectively. The corresponding electronic transport mechanisms are analyzed in detail. Our calculation results demonstrate that these investigated organic single-molecule nanojunctions have the potential applications in rectifiers and molecular wires. BibTeX: @book{An2016, title = {Rectifications in organic single-molecule diodes alkanethiolate-terminated heterocyclics}, author = {An, Yipeng and Zhang, Mengjun and Wang, Tianxing and Wang, Guangtao and Fu, Zhaoming}, booktitle = {Physics Letters A}, publisher = {Elsevier B.V.}, volume = {380}, number = {7-8}, pages = {923--926}, year = {2016}, keywords = {Charge transport,First-principles calculation,Molecular device,Nanoscale electronics,Non-equilibrium Green's function,Rectifier,area:molecular electronics}, area = {molecular electronics} doi = {10.1016/j.physleta.2015.12.035}, }  Golibjon R. Berdiyorov, Ali Kachmar, Fedwa El-Mellouhi, Marcelo A. Carignano & Mohamed El-Amine Madjet, Role of Cations on the Electronic Transport and Optical Properties of Lead-Iodide Perovskites, The Journal of Physical Chemistry C, Vol. 120(30), pp. 16259--16270 (2016) area:interfaces,perovskites interfaces Abstract: Using density functional theory in combination with the nonequilibrium Green's function formalism we study the role of organic (methylammonium, MA) and inorganic (cesium, Cs) cations on the electronic transport and optical properties of single crystal lead-iodide perovskite. Both dispersive interactions (i.e., van der Waals interactions) and spin–orbit coupling are taken into account in describing the properties of the considered systems. Despite sizable difference in the lattice parameters and the electric polarization of the system, both MAPbI3 and CsPbI3 show similar electronic transport properties. A small difference in the transmission originates from the variations of the electrostatic potential along the electronic transport direction. These two samples also exhibit similar optical and dielectric properties when they are in the same crystalline phase. Our finite temperature first-principles molecular dynamics simulations in combination with static density functional theory calculations also reveal ... BibTeX: @article{Berdiyorov2016g, title = {Role of Cations on the Electronic Transport and Optical Properties of Lead-Iodide Perovskites}, author = {Berdiyorov, Golibjon R. and Kachmar, Ali and El-Mellouhi, Fedwa and Carignano, Marcelo A. and El-Amine Madjet, Mohamed}, journal = {The Journal of Physical Chemistry C}, volume = {120}, number = {30}, pages = {16259--16270}, year = {2016}, keywords = {area:interfaces,perovskites}, area = {interfaces} doi = {10.1021/acs.jpcc.6b01818}, }  Chang-Ming Tan, Yan-Hong Zhou, Chang-Yong Chen, Ji-Feng Yu & Ke-Qiu Chen, Spin filtering and rectifying effects in the zinc methyl phenalenyl molecule between graphene nanoribbon leads, Organic Electronics, Vol. 28 pp. 244--251 (2016) Density-function theory,ELECTRIC-FIELD,JUNCTIONS,MAGNETORESISTANCE,Molecular device,Rectifying behaviors,Spin-filtering,TRANSPORT,ZIGZAG,area:graphene,area:molecular electronics graphene,molecular electronics Abstract: The molecule zinc methyl phenalenyl (ZMP), which is a neutral planar phenalenyl-based molecule, has been successfully synthesized experimentally, and large magnetic anisotropy was demonstrated when it is grown on the ferromagnetic metal surface [K. V. Raman et al. Nature, 2013, 493, 509]. Here, by using nonequilibrium Green's functions combined with the density functional theory, we investigate the electronic transport properties in the ZMP molecule coupled to graphene nanoribbon (GNR) leads. When the ZMP molecule is linked to zigzag GNR (ZGNR) electrodes, perfect spin-filtering effect and large spin-rectifying effect are found. And when the ZMP molecule is coupled to armchair GNR (AGNR) electrodes, rectifying effect is obtained and the rectifying directions can be manipulated by substituting the hydrogen atoms at the edge of ZMP molecule with atoms oxygen or nitrogen. The above interesting properties can be used for the next generation nanoscale device. Analyses are proposed for these phenomena. BibTeX: @article{Tan2016, title = {Spin filtering and rectifying effects in the zinc methyl phenalenyl molecule between graphene nanoribbon leads}, author = {Tan, Chang-Ming and Zhou, Yan-Hong and Chen, Chang-Yong and Yu, Ji-Feng and Chen, Ke-Qiu}, journal = {Organic Electronics}, publisher = {Elsevier B.V}, volume = {28}, pages = {244--251}, year = {2016}, keywords = {Density-function theory,ELECTRIC-FIELD,JUNCTIONS,MAGNETORESISTANCE,Molecular device,Rectifying behaviors,Spin-filtering,TRANSPORT,ZIGZAG,area:graphene,area:molecular electronics}, area = {graphene,molecular electronics} doi = {10.1016/j.orgel.2015.10.038}, }  Dan Zhang, Mengqiu Long, Xiaojiao Zhang, Jun Ouyang, Hui Xu & KowkSum Chan, Spin-resolved transport properties in zigzag α-graphyne nanoribbons with symmetric and asymmetric edge fluorinations, RSC Adv., Vol. 6(18), pp. 15008--15015 (2016) area:2dmat,graphyne nanoribbon 2dmat Abstract: Using the non-equilibrium Green's function method and the spin-polarized density functional theory, we investigate the stability and spin-resolved electronic transport properties of zigzag α-graphyne nanoribbons (ZαGYNRs) with symmetric (F-ZαGYNRs-F) and asymmetric (F2-ZαGYNRs-F) edge fluorinations. Our results show edge fluorination can enhance the stability of ZαGYNRs. The spin-resolved transport calculations reveal that the devices of F-ZαGYNRs-F with odd ribbon widths behave as a conductor with a linear current–voltage relationship, while the semiconductor property and perfect bipolar spin-filtering effect can be observed in those devices with even ribbon widths. In contrast, the spin-resolved transport properties of the asymmetric edge fluorinated F2-ZαGYNRs-F systems are independent of the ribbon width. Moreover, the F2-ZαGYNRs-F device is a perfect spin device with nearly 100% bipolar spin-filtering and spin negative differential resistance effects in a wide bias voltage region. And the magnetoresistance effect with the order of 106 and the spin rectification ratio as high as 108 have also been predicted. These phenomena suggest ZαGYNRs with asymmetric edge fluorination can be considered as a promising candidate material for nano-electronics and spintronics. BibTeX: @article{Zhang2016a, title = {Spin-resolved transport properties in zigzag α-graphyne nanoribbons with symmetric and asymmetric edge fluorinations}, author = {Zhang, Dan and Long, Mengqiu and Zhang, Xiaojiao and Ouyang, Jun and Xu, Hui and Chan, KowkSum}, journal = {RSC Adv.}, publisher = {Royal Society of Chemistry}, volume = {6}, number = {18}, pages = {15008--15015}, year = {2016}, keywords = {area:2dmat,graphyne nanoribbon}, area = {2dmat} doi = {10.1039/C5RA26007H}, }  Z. Ji, R. Zhou, L.C. Lew Yan Voon & Y. Zhuang, Strain-Induced Energy Band Gap Opening in Two-Dimensional Bilayered Silicon Film, Journal of Electronic Materials, Vol. 45(10), pp. 5040--5047 (2016) area:2dmat,area:materials,bandgap,density functional,density functional theory,silicene,strain,two dimensional 2dmat,materials Abstract: This work presents a theoretical study of the structural and electronic properties of bilayered silicon film (BiSF) under in-plane biaxial strain/stress using density functional theory (DFT). Atomic structures of the two-dimensional (2-D) silicon films are optimized by using both the local-density approximation (LDA) and generalized gradient approximation (GGA). In the absence of strain/stress, five buckled hexagonal honeycomb structures of the BiSF with triangular lattice have been obtained as local energy minima, and their structural stability has been verified. These structures present a Dirac-cone shaped energy band diagram with zero energy band gaps. Applying a tensile biaxial strain leads to a reduction of the buckling height. Atomically flat structures with zero buckling height have been observed when the AA-stacking structures are under a critical biaxial strain. Increase of the strain between 10.7% and 15.4% results in a band-gap opening with a maximum energy band gap opening of ∼0.17 eV, obtained when a 14.3% strain is applied. Energy band diagrams, electron transmission efficiency, and the charge transport property are calculated. Additionally, an asymmetric energetically favorable atomic structure of BiSF shows a non-zero band gap in the absence of strain/stress and a maximum band gap of 0.15 eV as a −1.71% compressive strain is applied. Both tensile and compressive strain/stress can lead to a band gap opening in the asymmetric structure. BibTeX: @article{Ji2016, title = {Strain-Induced Energy Band Gap Opening in Two-Dimensional Bilayered Silicon Film}, author = {Ji, Z. and Zhou, R. and Lew Yan Voon, L. C. and Zhuang, Y.}, journal = {Journal of Electronic Materials}, volume = {45}, number = {10}, pages = {5040--5047}, year = {2016}, keywords = {area:2dmat,area:materials,bandgap,density functional,density functional theory,silicene,strain,two dimensional}, area = {2dmat,materials} doi = {10.1007/s11664-016-4682-3}, }  G.R. Berdiyorov & M.E. Madjet, Structural, electronic transport and optical properties of functionalized quasi-2D TiC2 from first-principles calculations, Applied Surface Science, Vol. 390 pp. 1009--1014 (2016) Optical properties,area:2dmat,density functional theory,electronic transport,surface functionalization 2dmat Abstract: Using the first-principles density functional theory, we study the effect of surface functionalization on the structural and optoelectronic properties of recently proposed quasi-two-dimensional material TiC2 [T. Zhao, S. Zhang, Y. Guo, Q. Wang, Nanoscale 8 (2016) 233]. Hydrogenated, fluorinated, oxidized and hydroxylated surfaces are considered. Significant changes in the lattice parameters and partial charge distributions are found due to the surface termination. Direct contribution of the adatoms to the system density of states near the Fermi level is obtained, which has a major impact on the optoelectronic properties of the material. For example, surface termination results in larger absorption in the visible range of the spectrum. The electronic transport is also affected by the surface functionalization: the current in the system can be reduced by an order of magnitude. These findings indicate the importance of the effects of surface passivation on optoelectronic properties of this quasi-2D material. BibTeX: @article{Berdiyorov2016f, title = {Structural, electronic transport and optical properties of functionalized quasi-2D TiC2 from first-principles calculations}, author = {Berdiyorov, G.R. and Madjet, M.E.}, journal = {Applied Surface Science}, publisher = {Elsevier B.V.}, volume = {390}, pages = {1009--1014}, year = {2016}, keywords = {Optical properties,area:2dmat,density functional theory,electronic transport,surface functionalization}, area = {2dmat} doi = {10.1016/j.apsusc.2016.08.179}, }  S.M. Biswal, B. Baral, D. De & A. Sarkar, Study of effect of gate-length downscaling on the analog/RF performance and linearity investigation of InAs-based nanowire Tunnel FET, Superlattices and Microstructures, Vol. 91 pp. 319--330 (2016) 1-dB compression point,Cut-off frequency gain bandwidth product,InAs Tunnel FET,Transconductance,Transconductance generation factor,area:nanowires,area:semi nanowires,semi Abstract: In this paper, we present a simulation study to report the effect of gate-length downscaling on the analog/RF performance and linearity investigation of InAs-based nanowire (NW) Tunnel FET (TFET). The different RF/analog and linearity figure of merits such as gm, RO, gm∗RO, fT, fmax, GBW and 1-dB compression point of a NW TFET are extracted and the influence of gate-length downscaling on these parameters is analyzed. The RF/analog performance parameters obtained from InAs TFET is compared with an InAs MOSFET of identical dimension. Results reveal that superior RF and Linearity performance was obtained with gate-length downscaling for both devices under consideration. However, advantages of achieving improved RF performance with gate-length downscaling diminishes in terms of poor analog performance with gate-length downscaling for both the devices. This clearly indicates a trade-off between the analog and RF performance of a down-scaled InAs-based NW TFET and MOSFET. The results reveal that InAs TFET provides better fT, fmax and linearity performance in the saturation region than its MOSFET counterpart. It provides a reasonable RO, gm∗RO at lower values of gate-overdrive voltage as compared to the InAs MOSFET. Therefore, this paper concludes that InAs NW TFETs have enormous potential to be a promising contender to the conventional bulk MOSFETs for realization of future generation low-power analog/RF applications. textcopyright 2016 Elsevier Ltd. All rights reserved. BibTeX: @article{Biswal2016, title = {Study of effect of gate-length downscaling on the analog/RF performance and linearity investigation of InAs-based nanowire Tunnel FET}, author = {Biswal, S M and Baral, B and De, D and Sarkar, A}, journal = {Superlattices and Microstructures}, publisher = {Elsevier Ltd}, volume = {91}, pages = {319--330}, year = {2016}, keywords = {1-dB compression point,Cut-off frequency gain bandwidth product,InAs Tunnel FET,Transconductance,Transconductance generation factor,area:nanowires,area:semi}, area = {nanowires,semi} doi = {10.1016/j.spmi.2016.01.021}, }  Sidong Lei, Xifan Wang, Bo Li, Jiahao Kang, Yongmin He, Antony George, Liehui Ge, Yongji Gong, Pei Dong, Zehua Jin, Gustavo Brunetto, Weibing Chen, Zuan-Tao Lin, Robert Baines, Douglas S. Galvão, Jun Lou, Enrique Barrera, Kaustav Banerjee, Robert Vajtai & Pulickel Ajayan, Surface functionalization of two-dimensional metal chalcogenides by Lewis acid-base chemistry, Nature Nanotechnology, Vol. 11(May), pp. 465--472 (2016) Electronic devices,Nanostructures,Two-dimensional materials,area:2dmat,area:tmd 2dmat,tmd Abstract: Precise control of the electronic surface states of two-dimensional (2D) materials could improve their versatility and widen their applicability in electronics and sensing. To this end, chemical surface functionalization has been used to adjust the electronic properties of 2D materials. So far, however, chemical functionalization has relied on lattice defects and physisorption methods that inevitably modify the topological characteristics of the atomic layers. Here we make use of the lone pair electrons found in most of 2D metal chalcogenides and report a functionalization method via a Lewis acid-base reaction that does not alter the host structure. Atomic layers of n-type InSe react with Ti(4+) to form planar p-type [Ti(4+)n(InSe)] coordination complexes. Using this strategy, we fabricate planar p-n junctions on 2D InSe with improved rectification and photovoltaic properties, without requiring heterostructure growth procedures or device fabrication processes. We also show that this functionalization approach works with other Lewis acids (such as B(3+), Al(3+) and Sn(4+)) and can be applied to other 2D materials (for example MoS2, MoSe2). Finally, we show that it is possible to use Lewis acid-base chemistry as a bridge to connect molecules to 2D atomic layers and fabricate a proof-of-principle dye-sensitized photosensing device. BibTeX: @article{Lei2016, title = {Surface functionalization of two-dimensional metal chalcogenides by Lewis acid-base chemistry}, author = {Lei, Sidong and Wang, Xifan and Li, Bo and Kang, Jiahao and He, Yongmin and George, Antony and Ge, Liehui and Gong, Yongji and Dong, Pei and Jin, Zehua and Brunetto, Gustavo and Chen, Weibing and Lin, Zuan-Tao and Baines, Robert and Galvão, Douglas S. and Lou, Jun and Barrera, Enrique and Banerjee, Kaustav and Vajtai, Robert and Ajayan, Pulickel}, journal = {Nature Nanotechnology}, volume = {11}, number = {May}, pages = {465--472}, year = {2016}, keywords = {Electronic devices,Nanostructures,Two-dimensional materials,area:2dmat,area:tmd}, area = {2dmat,tmd} doi = {10.1038/nnano.2015.323}, }  Kaoruho Sakata, Blanka Magyari-Köpe, Suyog Gupta, Yoshio Nishi, Anders Blom & Peter Deák, The effects of uniaxial and biaxial strain on the electronic structure of germanium, Computational Materials Science, Vol. 112 pp. 263--268 (2016) QWpaper,Strained Ge,area:materials,area:semi,semi,strain materials,semi Abstract: Abstract The effects of uniaxial and biaxial strain on the electronic structure of bulk germanium are investigated using density functional theory in conjunction with four approximations for the exchange correlation interaction: the local density approximation (LDA) and generalized gradient approximation (GGA) with on-site Hubbard corrections (LDA+U, GGA+U), the meta-GGA (MGGA), and the screened hybrid functional (HSE06). The band structure and, especially, the band gap of unstrained Ge are well reproduced by these methods. The results of LDA+U/GGA+U and MGGA show that a biaxial tensile strain above 1.5% turns Ge into a direct-gap (G-G) semiconductor, whereas the indirect G-L gap is maintained for uniaxial strain up to 3%. The HSE06 results confirm a similar trend, although the predicted critical strain is lower. The effective masses were also calculated and they were found to be in good agreement with experiments for bulk Ge. It is predicted that the masses at Gamma can be tuned to be smaller/larger by tensile/compressive strain in all directions. BibTeX: @article{Sakata2016, title = {The effects of uniaxial and biaxial strain on the electronic structure of germanium}, author = {Sakata, Kaoruho and Magyari-Köpe, Blanka and Gupta, Suyog and Nishi, Yoshio and Blom, Anders and Deák, Peter}, journal = {Computational Materials Science}, volume = {112}, pages = {263--268}, year = {2016}, keywords = {QWpaper,Strained Ge,area:materials,area:semi,semi,strain}, area = {materials,semi} doi = {10.1016/j.commatsci.2015.10.023}, }  Dipankar Saha & Santanu Mahapatra, Theoretical insights on the electro-thermal transport properties of monolayer MoS2 with line defects, Journal of Applied Physics, Vol. 119 pp. 134304 (2016) Charge carriers,Density functional theory,Monolayers,Phonons,Thermal conduction,area:2dmat,area:tmd 2dmat,tmd Abstract: Two dimensional (2D) materials demonstrate several novel electrical, mechanical, and thermal properties which are quite distinctive to those of their bulk form. Among many others, one important potential application of the 2D material is its use in the field of energy harvesting. Owing to that, here we present a detailed study on electrical as well as thermal transport of monolayer MoS2, in quasi ballistic regime. Besides the perfect monolayer in its pristine form, we also consider various line defects which have been experimentally observed in mechanically exfoliated MoS2 samples. For calculating various parameters related to the electrical transmission, we employ the non-equilibrium Green's function-density functional theory combination. However, to obtain the phonon transmission, we take help of the parametrized Stillinger-Weber potential which can accurately delineate the inter-atomic interactions for the monolayer MoS2. Due to the presence of line defects, we observed significant reductions in both the charge carrier and the phonon transmissions through a monolayer MoS2 flake. Moreover, we also report a comparative analysis showing the temperature dependency of the thermoelectric figure of merit values, as obtained for the perfect as well as the other defective 2D samples. (C) 2016 AIP Publishing LLC. BibTeX: @article{Saha2016a, title = {Theoretical insights on the electro-thermal transport properties of monolayer MoS2 with line defects}, author = {Saha, Dipankar and Mahapatra, Santanu}, journal = {Journal of Applied Physics}, volume = {119}, pages = {134304}, year = {2016}, keywords = {Charge carriers,Density functional theory,Monolayers,Phonons,Thermal conduction,area:2dmat,area:tmd}, area = {2dmat,tmd} doi = {10.1063/1.4945582}, }  Daisuke Hayashi, Tomohiro Ueda, Yusuke Nakai, Haruka Kyakuno, Yasumitsu Miyata, Takahiro Yamamoto, Takeshi Saito, Kenji Hata & Yutaka Maniwa, Thermoelectric properties of single-wall carbon nanotube films: Effects of diameter and wet environment, Applied Physics Express, Vol. 9(2), pp. 025102 (2016) Seebeck,area:nanotubes nanotubes Abstract: The Seebeck coefficient S and the electrical resistivity ρ of single-wall carbon nanotube (SWCNT) films were investigated as a function of the SWCNT diameter and carrier concentration. The S and ρ significantly changed in humid environments through p-type carrier doping. Experiments, combined with theoretical simulations based on the non-equilibrium Green's function theory, indicated that the power factor P can be increased threefold by the enrichment of semiconducting SWCNTs, but the nanotube diameter has little effect. The improvement of the film resistivity strongly enhances the film thermoelectric performance, manifested as increasing the value of P above 1200 µW/(mcenterdotK2). BibTeX: @article{Hayashi2016, title = {Thermoelectric properties of single-wall carbon nanotube films: Effects of diameter and wet environment}, author = {Hayashi, Daisuke and Ueda, Tomohiro and Nakai, Yusuke and Kyakuno, Haruka and Miyata, Yasumitsu and Yamamoto, Takahiro and Saito, Takeshi and Hata, Kenji and Maniwa, Yutaka}, journal = {Applied Physics Express}, volume = {9}, number = {2}, pages = {025102}, year = {2016}, keywords = {Seebeck,area:nanotubes}, area = {nanotubes} doi = {10.7567/APEX.9.025102}, }  Feras Al-Dirini, Mahmood A. Mohammed, Md Sharafat Hossain, Faruque M. Hossain, Ampalavanapillai Nirmalathas & Stan Skafidas, Tuneable graphene nanopores for single biomolecule detection, Nanoscale, Vol. 8 pp. 10066--10077 (2016) area:graphene,transmission pathways graphene Abstract: Solid-state nanopores are promising candidates for next generation DNA and protein sequencing. However, once fabricated, such devices lack tuneability, which greatly restricts their biosensing capabilities. Here we propose a new class of solid-state graphene-based nanopore devices that exhibit a unique capability of self-tuneability, which is used to control their conductance, tuning it to levels comparable to the changes caused by the translocation of a single biomolecule, and hence, enabling high detection sensitivities. Our presented quantum simulation results suggest that the smallest amino acid, glycine, when present in water and in an aqueous saline solution can be detected with high sensitivity, up to a 90% change in conductance. Our results also suggest that passivating the device with nitrogen, making it an n-type device, greatly enhances its sensitivity, and makes it highly sensitive to not only the translocation of a single biomolecule, but more interestingly to intramolecular electrostatics within the biomolecule. Sensitive detection of the carboxyl group within the glycine molecule, which carries a charge equivalent to a single electron, is achieved with a conductance change that reaches as high as 99% when present in an aqueous saline solution. The presented findings suggest that tuneable graphene nanopores, with their capability of probing intramolecular electrostatics, could pave the way towards a new generation of single biomolecule detection devices. BibTeX: @article{Al-Dirini2016, title = {Tuneable graphene nanopores for single biomolecule detection}, author = {Al-Dirini, Feras and Mohammed, Mahmood A and Hossain, Md Sharafat and Hossain, Faruque M and Nirmalathas, Ampalavanapillai and Skafidas, Stan}, journal = {Nanoscale}, volume = {8}, pages = {10066--10077}, year = {2016}, keywords = {area:graphene,transmission pathways}, area = {graphene} doi = {10.1039/C5NR05274B}, }  Zakaria Y. Al Balushi, Ke Wang, Ram Krishna Ghosh, Rafael A. Vilá, Sarah M. Eichfeld, Joshua D. Caldwell, Xiaoye Qin, Yu-Chuan Lin, Paul A. DeSario, Greg Stone, Shruti Subramanian, Dennis F. Paul, Robert M. Wallace, Suman Datta, Joan M. Redwing & Joshua A. Robinson, Two-dimensional gallium nitride realized via graphene encapsulation, Nature Materials, Vol. 15(11), pp. 1166--1171 (2016) Electronic properties and materials,Two-dimensional materials,area:2dmat,area:graphene 2dmat,graphene Abstract: The spectrum of two-dimensional (2D) and layered materials ‘beyond graphene' offers a remarkable platform to study new phenomena in condensed matter physics. Among these materials, layered hexagonal boron nitride (hBN), with its wide bandgap energy ( 5.0–6.0 eV), has clearly established that 2D nitrides are key to advancing 2D devices1. A gap, however, remains between the theoretical prediction of 2D nitrides ‘beyond hBN'2, 3 and experimental realization of such structures. Here we demonstrate the synthesis of 2D gallium nitride (GaN) via a migration-enhanced encapsulated growth (MEEG) technique utilizing epitaxial graphene. We theoretically predict and experimentally validate that the atomic structure of 2D GaN grown via MEEG is notably different from reported theory2, 3, 4. Moreover, we establish that graphene plays a critical role in stabilizing the direct-bandgap (nearly 5.0 eV), 2D buckled structure. Our results provide a foundation for discovery and stabilization of 2D nitrides that are difficult to prepare via traditional synthesis. BibTeX: @article{AlBalushi2016, title = {Two-dimensional gallium nitride realized via graphene encapsulation}, author = {Al Balushi, Zakaria Y. and Wang, Ke and Ghosh, Ram Krishna and Vilá, Rafael A. and Eichfeld, Sarah M. and Caldwell, Joshua D. and Qin, Xiaoye and Lin, Yu-Chuan and DeSario, Paul A. and Stone, Greg and Subramanian, Shruti and Paul, Dennis F. and Wallace, Robert M. and Datta, Suman and Redwing, Joan M. and Robinson, Joshua A.}, journal = {Nature Materials}, volume = {15}, number = {11}, pages = {1166--1171}, year = {2016}, keywords = {Electronic properties and materials,Two-dimensional materials,area:2dmat,area:graphene}, area = {2dmat,graphene} doi = {10.1038/nmat4742}, }  Jin-Kyu Choi, Hien Thu Pham & Hyun-Dam Jeong, A comparative study of electron transport in benzene molecule covalently bonded to gold and silicon electrodes for pioneering the electron transport properties of silicon quantum dot-molecule hybrid polymers, Current Applied Physics, Vol. 15(8), pp. 877--884 (2015) DFT,Electrode,Electron transport,NEGF,Semiconductor,Silicon,are,area:molecular electronics,quantum dots are,molecular electronics Abstract: In order to pioneer the electron transport properties of silicon (Si) quantum dot-molecule hybrid polymers, we investigate the electron transport properties of the benzene molecule in silicon (Si) semiconductor electrodes, based on nonequilibrium Green's function (NEGF) method coupled with density functional theory (DFT), in comparison with conventional gold (Au) metal electrodes, with three different anchoring linker groups: thiol for dithiol-benzene (DTB), methylene for dimethyl-benzene (DMB), and direct bonding for benzene (Ph). It is interestingly found that, due to band gap nature of the Si semiconductor electrodes, the molecular junctions with the Si electrodes show no current up to the bias voltage of around 0.8 V. In addition, the DTB molecular junctions in the Si semiconductor electrodes connected with Si-S bond show higher conducting properties than other DMB and Ph molecular junctions directly coupled to the electrodes with the Si-C bonds (DMB textless Ph textless DTB). The electron transport properties of the molecules in the two different electrodes are analyzed on the basis of the understanding transmission spectra, projected density of states (PDOS), and molecular orbitals. We believe that the use of thiol linker may open new possibility in the molecular electronics with the Si semiconductor electrodes and the Si QD-molecule hybrid polymers concept. BibTeX: @article{Choi2015, title = {A comparative study of electron transport in benzene molecule covalently bonded to gold and silicon electrodes for pioneering the electron transport properties of silicon quantum dot-molecule hybrid polymers}, author = {Choi, Jin-Kyu and Pham, Hien Thu and Jeong, Hyun-Dam}, journal = {Current Applied Physics}, volume = {15}, number = {8}, pages = {877--884}, year = {2015}, keywords = {DFT,Electrode,Electron transport,NEGF,Semiconductor,Silicon,are,area:molecular electronics,quantum dots}, area = {are,molecular electronics} doi = {10.1016/j.cap.2015.03.021}, }  Mahdi Ghorbani-Asl, Paul D. Bristowe & Krzysztof Koziol, A computational study of the quantum transport properties of a Cu-CNT composite, Physical Chemistry Chemical Physics, Vol. 17(28), pp. 18273--18277 (2015) area:interfaces,area:nanotubes interfaces,nanotubes Abstract: The quantum transport properties of a Cu-CNT composite are studied using a non-equilibrium Green's function approach combined with the self-consistent-charge density-functional tight-binding method. The results show that the electrical conductance of the composite depends strongly on CNT density and alignment but more weakly on chirality. Alignment with the applied bias is preferred and the conductance of the composite increases as its mass density increases. BibTeX: @article{Ghorbani-Asl2015, title = {A computational study of the quantum transport properties of a Cu-CNT composite}, author = {Ghorbani-Asl, Mahdi and Bristowe, Paul D and Koziol, Krzysztof}, journal = {Physical Chemistry Chemical Physics}, publisher = {The Royal Society of Chemistry}, volume = {17}, number = {28}, pages = {18273--18277}, year = {2015}, keywords = {area:interfaces,area:nanotubes}, area = {interfaces,nanotubes} doi = {10.1039/C5CP01470K}, }  Xiangru Kong, Dongqing Zou, Hui Wang, Xiaohui Jiang, Sun Yin, Dongmei Li & Desheng Liu, A first principle study on the spin transport properties in heterojunctions based on zigzag-edged graphene nanoribbons and graphitic carbon nitride nanoribbons, RSC Adv., Vol. 5(86), pp. 70682--70688 (2015) MAGNETORESISTANCE,NEGATIVE DIFFERENTIAL RESISTANCE,area:graphene,area:spin graphene,spin Abstract: By using non-equilibrium Green's functions (NEGF) and density functional theory (DFT), we investigate the spin-dependent electronic transport properties of two heterojunctions based on zigzag-edged graphene nanoribbons and graphitic carbon nitride nanoribbons. The only difference is the scattering region, i.e., one is zigzag-edged graphene nanoribbons (ZGNRs) and the other is graphitic carbon nitride (g-C3N4) nanoribbons. The I–V curves in the ferromagnetic and antiferromagnetic states for both devices are demonstrated. Our results show that the heterojunctions are promising multifunctional devices in molecular spintronics due to their nearly perfect spin-filtering efficiency (SFE) and high rectification ratio (RR). Spin negative differential resistance (SNDR) properties at low biases can also be found in the two devices. The mechanisms are proposed for these phenomena. The spin polarizations in the transmission spectra result in the nearly perfect SFE, the asymmetry in the structures gives rise to the high RR. Moreover, for the SNDR, the suppression of the transmission spectra is mainly caused by the localization in the total density of states. BibTeX: @article{Kong2015, title = {A first principle study on the spin transport properties in heterojunctions based on zigzag-edged graphene nanoribbons and graphitic carbon nitride nanoribbons}, author = {Kong, Xiangru and Zou, Dongqing and Wang, Hui and Jiang, Xiaohui and Yin, Sun and Li, Dongmei and Liu, Desheng}, journal = {RSC Adv.}, publisher = {Royal Society of Chemistry}, volume = {5}, number = {86}, pages = {70682--70688}, year = {2015}, keywords = {MAGNETORESISTANCE,NEGATIVE DIFFERENTIAL RESISTANCE,area:graphene,area:spin}, area = {graphene,spin} doi = {10.1039/C5RA09205A}, }  Hongmei Liu, Yuanyuan He, Jinjiang Zhang, Jianwei Zhao & Li Chen, A theoretical study of asymmetric electron transport through linearly aromatic molecules, Physical Chemistry Chemical Physics, Vol. 17(6), pp. 4558--4568 (2015) area:molecular electronics molecular electronics Abstract: Electron transport through a series of polyacene molecules connected via a [small pi]-conjugated bridge (an anthracene molecule) was investigated theoretically by using the nonequilibrium Green's function formalism combined with density functional theory. The results have shown that the asymmetric current-voltage characteristics can be achieved by tuning the position of a side [small pi]-bridge linked to the main conjugated backbone. The detailed analyses of the spatial distribution of molecular orbitals as well as the current density interpret how the location of [small pi]-bridge strongly affects the intramolecular electronic coupling. The rectification in the molecular junction arises from the localization of the molecular orbitals near the Fermi level and the asymmetric shift of molecule orbital energy levels under positive and negative bias. The rectification ratio decreases with increasing the length of the [small pi]-bridge which improves intramolecular electronic coupling between aromatic rings. Furthermore, the rectification properties of conjugated molecules are just slightly affected by the anchoring positions of thiol groups. These results demonstrated that the location and the length of [small pi]-bridge, which induce the asymmetric intramolecular coupling, play key roles in the rectification of the linearly aromatic molecules. BibTeX: @article{Liu2015, title = {A theoretical study of asymmetric electron transport through linearly aromatic molecules}, author = {Liu, Hongmei and He, Yuanyuan and Zhang, Jinjiang and Zhao, Jianwei and Chen, Li}, journal = {Physical Chemistry Chemical Physics}, publisher = {The Royal Society of Chemistry}, volume = {17}, number = {6}, pages = {4558--4568}, year = {2015}, keywords = {area:molecular electronics}, area = {molecular electronics} doi = {10.1039/C4CP03887H}, }  Jing Zeng & Ke-Qiu Chen, Abnormal oscillatory conductance and strong odd-even dependence of a perfect spin-filtering effect in a carbon chain-based spintronic device, J. Mater. Chem. C, Vol. 3(22), pp. 5697--5702 (2015) area:spin spin Abstract: By using nonequilibrium Green's functions in combination with the density functional theory, the transport properties of a carbon chain-based spintronic device are investigated. Previous reports show that when the carbon chains are sandwiched between metal electrodes or perfect zigzag graphene nanoribbons, the conductance of odd-n carbon chain systems is higher than that of even-n ones [Phys. Rev. Lett., 1998, 81, 3515; J. Am. Chem. Soc., 2010, 132, 11481-11486]. However, when the carbon chains are connected with Fe-porphyrin-like armchair graphene nanoribbons, we find that low conductance states belong to odd-n carbon chain systems while large conductance states belong to even-n carbon chain systems, indicating abnormal oscillatory conductance. Moreover, we also find that when the spin polarization is considered, the oscillatory characteristic of conductance in the spin-up state is opposite to that in the spin-down state. Especially, the perfect spin-filtering effect appears only in the odd-n carbon chain systems, showing a strong odd-even dependence characteristic. The mechanisms are suggested for these interesting phenomena. BibTeX: @article{Zeng2015, title = {Abnormal oscillatory conductance and strong odd-even dependence of a perfect spin-filtering effect in a carbon chain-based spintronic device}, author = {Zeng, Jing and Chen, Ke-Qiu}, journal = {J. Mater. Chem. C}, publisher = {The Royal Society of Chemistry}, volume = {3}, number = {22}, pages = {5697--5702}, year = {2015}, keywords = {area:spin}, area = {spin} doi = {10.1039/C5TC00756A}, }  Pankaj Srivastava, Varun Sharma & Neeraj K. Jaiswal, Adsorption of COCl2 gas molecule on armchair boron nitride nanoribbons for nano sensor applications, Microelectronic Engineering, Vol. 146 pp. 62--67 (2015) Boron nitride,Electronic band structure,Nanoribbons,Sensor,Transmission spectra,area:materials,area:semi materials,semi Abstract: First-principle calculations under the framework of density functional theory have been performed to study the adsorption of COCl2 (Phosgene) gas molecule on armchair boron nitride nanoribbon (ABNNR). Depending upon the geometry of the ribbon, we have considered two possible cases for adsorption of guest molecule i.e. adsorption at closed edge and adsorption at open edge. Adsorption energy (Ead) calculations implies that adsorption at open edge is energetically more favorable compared to closed edge case. The formation of closed ring structure at the open edge in this case also accounts for its stability. Electronic properties reveal that with the adsorption of COCl2 molecule on ABNNR the semiconducting behavior remains intact but a significant modulation in the band gap is observed as compared to bare ribbon. The current voltage (I-V) characteristics have also been investigated using non-equilibrium green's function (NEGF) approach. The results indicate towards the potential applicability of ABNNR for sensing the toxic COCl2 gas. BibTeX: @article{Srivastava2015a, title = {Adsorption of COCl2 gas molecule on armchair boron nitride nanoribbons for nano sensor applications}, author = {Srivastava, Pankaj and Sharma, Varun and Jaiswal, Neeraj K}, journal = {Microelectronic Engineering}, volume = {146}, pages = {62--67}, year = {2015}, keywords = {Boron nitride,Electronic band structure,Nanoribbons,Sensor,Transmission spectra,area:materials,area:semi}, area = {materials,semi} doi = {10.1016/j.mee.2015.03.040}, }  Yangyang Wang, Zeyuan Ni, Qihang Liu, Ruge Quhe, Jiaxin Zheng, Meng Ye, Dapeng Yu, Junjie Shi, Jinbo Yang, Ju Li & Jing Lu, All-Metallic Vertical Transistors Based on Stacked Dirac Materials, Advanced Functional Materials, Vol. 25(1), pp. 68--77 (2015) Dirac materials,area:2dmat,area:interfaces,density functional theory,field effect transistor,quantum transport,vertical heterostructure 2dmat,interfaces Abstract: It is an ongoing pursuit to use metal as a channel material in a field effect transistor. All metallic transistor can be fabricated from pristine semimetallic Dirac materials (such as graphene, silicene, and germanene), but the on/off current ratio is very low. In a vertical heterostructure composed by two Dirac materials, the Dirac cones of the two materials survive the weak interlayer van der Waals interaction based on density functional theory method, and electron transport from the Dirac cone of one material to the one of the other material is therefore forbidden without assistance of phonon because of momentum mismatch. First-principles quantum transport simulations of the all-metallic vertical Dirac material heterostructure devices confirm the existence of a transport gap of over 0.4 eV, accompanied by a switching ratio of over 10^4. Such a striking behavior is robust against the relative rotation between the two Dirac materials and can be extended to twisted bilayer graphene. Therefore, all-metallic junction can be a semiconductor and novel avenue is opened up for Dirac material vertical structures in high-performance devices without opening their band gaps. BibTeX: @article{Wang2015, title = {All-Metallic Vertical Transistors Based on Stacked Dirac Materials}, author = {Wang, Yangyang and Ni, Zeyuan and Liu, Qihang and Quhe, Ruge and Zheng, Jiaxin and Ye, Meng and Yu, Dapeng and Shi, Junjie and Yang, Jinbo and Li, Ju and Lu, Jing}, journal = {Advanced Functional Materials}, volume = {25}, number = {1}, pages = {68--77}, year = {2015}, keywords = {Dirac materials,area:2dmat,area:interfaces,density functional theory,field effect transistor,quantum transport,vertical heterostructure}, area = {2dmat,interfaces} doi = {10.1002/adfm.201402904}, }  Bahniman Ghosh & Naval Kishor, An ab initio study of strained two-dimensional MoSe2, Journal of Semiconductors, Vol. 36(4), pp. 43001 (2015) MoSe2,area:tmd,band structure,self-consistent calculation tmd Abstract: We have studied the electronic properties of molybdenum diselenide (MoSe2) in both bulk and monolayer (zigzag and armchair) forms using density function theory. The metallic nature of the zigzag MoSe2 (ZMoSe2) nanoribbon and the semiconducting behavior of the armchair MoSe2 (AMoSe2) nanoribbon have been explored using a band structure calculated using self-consistent calculations. We have also studied the variation in the bandgap in the presence of a small amount of strain (uniaxial, biaxial). The effect of tensile strain has been investigated and shifts in the conduction band and valance band have been observed with different amounts of applied strain. BibTeX: @article{Ghosh2015, title = {An ab initio study of strained two-dimensional MoSe2}, author = {Ghosh, Bahniman and Kishor, Naval}, journal = {Journal of Semiconductors}, volume = {36}, number = {4}, pages = {43001}, year = {2015}, keywords = {MoSe2,area:tmd,band structure,self-consistent calculation}, area = {tmd} doi = {10.1088/1674-4926/36/4/043001}, }  Abbas Arab & Qiliang Li, Anisotropic thermoelectric behavior in armchair and zigzag mono- and fewlayer MoS2 in thermoelectric generator applications, Vol. 5 pp. 13706 (2015) area:2dmat,area:thermo,area:tmd 2dmat,thermo,tmd Abstract: In this work, we have designed and simulated new thermoelectric generator based on monolayer and few-layer MoS2 nanoribbons. The proposed thermoelectric generator is composed of thermocouples made of both n-type and p-type MoS2 nanoribbon legs. Density Functional Tight-Binding Non-Equilibrium Green's Function (DFTB-NEGF) method has been used to calculate the transmission spectrum of MoS2 armchair and zigzag nanoribbons. Phonon transmission spectrum are calculated based on parameterization of Stillinger-Weber potential. Thermoelectric figure of merit, ZT, is calculated using these electronic and phonon transmission spectrum. Monolayer and bilayer MoS2 armchair nanoribbons are found to have the highest ZT value for p-type and n-type legs, repectively. Moreover, we have compared the thermoelectric current of doped monolayer MoS2 armchair nanoribbons and SZi thin films. Results indicate that thermoelectric current of MoS2 monolayer nanoribbons is several orders of magnitude higher than that of Si thin films. BibTeX: @inproceedings{Arab2015, title = {Anisotropic thermoelectric behavior in armchair and zigzag mono- and fewlayer MoS2 in thermoelectric generator applications}, author = {Arab, Abbas and Li, Qiliang}, booktitle = {Scientific Reports}, volume = {5}, pages = {13706}, year = {2015}, keywords = {area:2dmat,area:thermo,area:tmd}, area = {2dmat,thermo,tmd} doi = {10.1038/srep13706}, }  Sadegh Mehdi Aghaei & Irene Calizo, Band gap tuning of armchair silicene nanoribbons using periodic hexagonal holes, Journal of Applied Physics, Vol. 118(10), pp. 104304 (2015) Band gap,Band structure,Dangling bonds,Graphene,Nanomaterials,area:2dmat,area:graphene 2dmat,graphene Abstract: The popularity of graphene owing to its unique and exotic properties has triggered a great deal of interest in other two-dimensional nanomaterials. Among them silicene shows considerable promise for electronic devices with a carrier mobility comparable to graphene, flexible buckled structure, and expected compatibility with silicon electronics. Using first-principle calculations based on density functional theory, the electronic properties of armchair silicene nanoribbons perforated with periodic nanoholes (ASiNRPNHs) are investigated. Two different configurations of mono-hydrogenated (:H) and di-hydrogenated (:2H) silicene edges are considered. Pristine armchair silicene nanoribbons (ASiNRs) can be categorized into three branches with width W = 3P − 1, 3P, and 3P + 1, P is an integer. The order of their energy gaps change from “EG (3P − 1) textless EG (3P) textless EG (3P + 1)” for W-ASiNRs:H to “EG (3P + 1) textless EG (3P − 1) textless EG (3P)” for W-ASiNRs:2H. We found the band gaps of W-ASiNRs:H and (W + 2)-ASiNRs:2H are slightly different, giving larger band gaps for wider ASiNRs:2H. ASiNRPNHs' band gaps changed based on the nanoribbon's width, nanohole's repeat periodicity and position relative to the nanoribbon's edge compared to pristine ASiNRs because of changes in quantum confinement strength. ASiNRPNHs:2H are more stable than ASiNRPNHs:H and their band gaps are noticeably greater than ASiNRPNHs:H. We found that the value of energy band gap for 12-ASiNRPNHs:2H with repeat periodicity of 2 is 0.923 eV. This value is about 2.2 times greater than pristine ASiNR:2H and double that of the 12-ASiNRPNHs:H with repeat periodicity of 2. BibTeX: @article{MehdiAghaei2015, title = {Band gap tuning of armchair silicene nanoribbons using periodic hexagonal holes}, author = {Mehdi Aghaei, Sadegh and Calizo, Irene}, journal = {Journal of Applied Physics}, volume = {118}, number = {10}, pages = {104304}, year = {2015}, keywords = {Band gap,Band structure,Dangling bonds,Graphene,Nanomaterials,area:2dmat,area:graphene}, area = {2dmat,graphene} doi = {10.1063/1.4930139}, }  Y. Min, J.H. Fang, C.G. Zhong, Z.C. Dong, Z.Y. Zhao, P.X. Zhou & K.L. Yao, Bias changing molecule-lead couple and inducing low bias negative differential resistance for electrons acceptor predicted by first-principles study, Physics Letters A, Vol. 379(40-41), pp. 2637--2640 (2015) First-principles,Molecular electronics,Non-equil,area:molecular electronics molecular electronics Abstract: A first-principles study of the transport properties of 3,13-dimercaptononacene-6,21-dione molecule sandwiched between two gold leads is reported. The strong effect of negative differential resistance with large peak-to-valley ratio of 710% is present under low bias. We found that bias can change molecule-lead couple and induce low bias negative differential resistance for electrons acceptor, which may promise the potential applications in molecular devices with low-power dissipation in the future. BibTeX: @article{Min2015, title = {Bias changing molecule-lead couple and inducing low bias negative differential resistance for electrons acceptor predicted by first-principles study}, author = {Min, Y and Fang, J H and Zhong, C G and Dong, Z C and Zhao, Z Y and Zhou, P X and Yao, K L}, journal = {Physics Letters A}, volume = {379}, number = {40-41}, pages = {2637--2640}, year = {2015}, keywords = {First-principles,Molecular electronics,Non-equil,area:molecular electronics}, area = {molecular electronics} doi = {10.1016/j.physleta.2015.06.007}, }  Li Hua Wang, Zi Zhen Zhang, Jian Guo Zhao, Bing Jun Ding, Yong Guo & Chun Jin, Bipolar spin-filtering effect in B- or N-doped zigzag graphene nanoribbons with asymmetric edge hydrogenation, Physics Letters, Section A: General, Atomic and Solid State Physics, Vol. 379(43-44), pp. 2860--2865 (2015) Density functional theory,Graphene,Non-equilibrium Green's function,Spin-filtering,area:graphene,area:spin graphene,spin Abstract: The spin transport properties of zigzag graphene nanoribbon (ZGNR) hetero-junctions, in which ZGNR electrodes are doped with B or N atoms, are investigated based on spin-polarized density functional theory and non-equilibrium Green's function. ZGNRs are C-H2 bonded at one edge and C-H bonded at the other edge to form asymmetric edge hydrogenation. The spin-polarized currents of ZGNR-based nano-devices with an odd or even number of the zigzag-shaped chains show a perfect bipolar spin-filtering effect on parallel and anti-parallel magnetic configurations. This study provides insights into the design of high-performance graphene-based spin filters. BibTeX: @article{Wang2015a, title = {Bipolar spin-filtering effect in B- or N-doped zigzag graphene nanoribbons with asymmetric edge hydrogenation}, author = {Wang, Li Hua and Zhang, Zi Zhen and Zhao, Jian Guo and Ding, Bing Jun and Guo, Yong and Jin, Chun}, journal = {Physics Letters, Section A: General, Atomic and Solid State Physics}, publisher = {Elsevier B.V.}, volume = {379}, number = {43-44}, pages = {2860--2865}, year = {2015}, keywords = {Density functional theory,Graphene,Non-equilibrium Green's function,Spin-filtering,area:graphene,area:spin}, area = {graphene,spin} doi = {10.1016/j.physleta.2015.09.020}, }  Yan Hong Zhou, Chang Yong Chen, Bo Lin Li & Ke Qiu Chen, Characteristics of classical Kirchhoff's superposition law in carbon atomic wires connected in parallel, Carbon, Vol. 95 pp. 503--510 (2015) Carbon atomic wire,Classical Kirchhoff's superposition law,Quantum interference,Spin filtering effect,area:nanowires nanowires Abstract: The classical Kirchhoff's superposition law is hard to realize in the molecular scale devices because the coupling between the juxtaposed molecules can lead to constructive or destructive quantum interferences [Vazquez et al. nature nanotechnology 2012, 7, 663; Zhu et al. Phys. Rev. B 2014, 89, 085427]. In view of this, we try to eliminate the quantum interference between the juxtaposed molecules by increasing the distance between them. Simple junctions of carbon atomic wire(s) coupled to zigzag graphene nanoribbon electrodes are chosen as our model. Interestingly, fine Kirchhoff's superposition law phenomenon is found when the distance between the two carbon atomic wires reaches 15.5 ??. At the distance 15.5 ??, the conductance for the double carbon atomic wire (DCAW) configuration is 1.96 times of that for single carbon atomic wire (SCAW) configuration and the current across the DCAW configuration keeps nearly two times of that across the SCAW configuration at the applied biases. In addition, the conductance superposition effect becomes better when the distance between the two wires increases further and the spin filtering effect is enhanced in the DCAW configuration. BibTeX: @article{Zhou2015c, title = {Characteristics of classical Kirchhoff's superposition law in carbon atomic wires connected in parallel}, author = {Zhou, Yan Hong and Chen, Chang Yong and Li, Bo Lin and Chen, Ke Qiu}, journal = {Carbon}, publisher = {Elsevier Ltd}, volume = {95}, pages = {503--510}, year = {2015}, keywords = {Carbon atomic wire,Classical Kirchhoff's superposition law,Quantum interference,Spin filtering effect,area:nanowires}, area = {nanowires} doi = {10.1016/j.carbon.2015.08.064}, }  Jing Huang, Rong Xie, Weiyi Wang, Qunxiang Li & Jinlong Yang, Coherent transport through spin-crossover magnet Fe2 complexes, Nanoscale, Vol. 8 pp. 609--616 (2015) CLUSTERS,DEVICES,ELECTRONICS,FE(II) COMPLEXES,GRAPHENE,MOLECULAR SPINTRONICS,SINGLE-MOLECULE,SPECTROSCOPY,SYSTEMS,area:molecular electronics,area:spin molecular electronics,spin Abstract: As one of the most promising building blocks in molecular spintronics, spin crossover (SCO) complexes have attracted increasing attention due to their magnetic bistability between the high-spin (HS) and low-spin (LS) states. Here, we explore the electronic structures and transport properties of SCO magnet Fe2 complexes with three different spin-pair configurations, namely [LS–LS], [LS–HS], and [HS–HS], by performing extensive density functional theory calculations combined with the non-equilibrium Green's function technique. Our calculations clearly reveal that the SCO magnet Fe2 complexes should display two-step spin transitions triggered by external stimuli, i.e. temperature or light, which confirm the previous phenomenological model and agree well with previous experimental measurements. Based on the calculated transport results, we observe a nearly perfect spin-filtering effect and negative differential resistance (NDR) behavior integrated in the SCO magnet Fe2 junction with the [HS–HS] configuration. The current through the [HS–HS] SCO magnet Fe2 complex under a small bias voltage is mainly contributed by the spin-down electrons, which is significantly larger than those of the [LS–LS] and [LS–HS] cases. The bias-dependent transmissions are responsible for the observed NDR effect. These theoretical findings suggest that SCO Fe2 complexes hold potential applications in molecular spintronic devices. BibTeX: @article{Huang2015, title = {Coherent transport through spin-crossover magnet Fe2 complexes}, author = {Huang, Jing and Xie, Rong and Wang, Weiyi and Li, Qunxiang and Yang, Jinlong}, journal = {Nanoscale}, publisher = {Royal Society of Chemistry}, volume = {8}, pages = {609--616}, year = {2015}, keywords = {CLUSTERS,DEVICES,ELECTRONICS,FE(II) COMPLEXES,GRAPHENE,MOLECULAR SPINTRONICS,SINGLE-MOLECULE,SPECTROSCOPY,SYSTEMS,area:molecular electronics,area:spin}, area = {molecular electronics,spin} doi = {10.1039/c5nr05601b}, }  Y. Min, J.H. Fang, C.G. Zhong, Z.C. Dong, J.F. Li, K.L. Yao & L.P. Zhou, Contact transparency inducing low bias negative differential resistance in two capped carbon nanotubes sandwiching sigma barrier, Applied Physics A, Vol. 118(1), pp. 367--371 (2015) area:nanotubes,carbon nanotube,contact,negative differenaial resistance nanotubes Abstract: A first-principles study of the transport properties of two capped (5, 5) carbon nanotubes sandwiching sigma barrier is reported. Contact transparency at zero bias is obtained. Strong negative differential resistance effect with large peak-to-valley ratio of 1,124 % is present under very low bias, which may promise the potential applications in nano-electronic devices with low power dissipation in the future. BibTeX: @article{Min2015b, title = {Contact transparency inducing low bias negative differential resistance in two capped carbon nanotubes sandwiching sigma barrier}, author = {Min, Y and Fang, J H and Zhong, C G and Dong, Z C and Li, J F and Yao, K L and Zhou, L P}, journal = {Applied Physics A}, publisher = {Springer Berlin Heidelberg}, volume = {118}, number = {1}, pages = {367--371}, year = {2015}, keywords = {area:nanotubes,carbon nanotube,contact,negative differenaial resistance}, area = {nanotubes} doi = {10.1007/s00339-014-8743-2}, }  Yun Zou, Mengqiu Long, Mingjun Li, Xiaojiao Zhang, Qingtian Zhang & Hui Xu, Control of electronic transport in nanohole defective zigzag graphene nanoribbon by means of side alkene chain, RSC Advances, Vol. 5(25), pp. 19152--19158 (2015) MAGNETORESISTANCE,NEGATIVE DIFFERENTIAL RESISTANCE,STANDING WAVES,area:graphene,area:molecular electronics graphene,molecular electronics Abstract: Using the nonequilibrium Green function formalism combined with density functional theory, we studied the electronic transport properties of nanohole defective zigzag graphene nanoribbon (ZGNR) junctions. A side alkene chain is connected to the edge of the defective ZGNR in the scattering region. We find that the transport properties of the defective ZGNR junction are strongly dependent on the parity of the number of carbon atoms in the side alkene chain. The side chain can switch on (even) and off (odd) the transport channel of our proposed junction. It is found that the transmissions for the side chains with an even number of carbon atoms are around 2G0, but they are around 1G0 for the side chains with an odd number of carbon atoms. The origin of this peculiar behavior is analyzed as due to the electronic states at the edge of the defective ZGNR which are modulated by the side-chain length. Our theoretical study shows that it is feasible to control the conduction of ZGNR by changing the side-chain length via external modulations such as chemical methods, which may stimulate experimental investigations in the future. BibTeX: @article{Zou2015, title = {Control of electronic transport in nanohole defective zigzag graphene nanoribbon by means of side alkene chain}, author = {Zou, Yun and Long, Mengqiu and Li, Mingjun and Zhang, Xiaojiao and Zhang, Qingtian and Xu, Hui}, journal = {RSC Advances}, publisher = {The Royal Society of Chemistry}, volume = {5}, number = {25}, pages = {19152--19158}, year = {2015}, keywords = {MAGNETORESISTANCE,NEGATIVE DIFFERENTIAL RESISTANCE,STANDING WAVES,area:graphene,area:molecular electronics}, area = {graphene,molecular electronics} doi = {10.1039/C4RA12924E}, }  Jie Ma, Chuan-Lu Yang, Mei-Shan Wang & Xiao-Guang Ma, Controlling the electronic transport properties of the tetrapyrimidinyl molecule with atom modified sulfur bridge, RSC Advances, Vol. 5(14), pp. 10675--10679 (2015) area:molecular electronics molecular electronics Abstract: The effect of the modified sulfur bridge on the I-V characteristics of a two-probe system of tetrapyrimidinyl molecules and Au electrodes is explored based on density functional theory with nonequilibrium Green's function. Five modified sulfur bridges with H, N or O atoms are considered. The two-probe system demonstrates a switch behavior when the sulfur bridge is modified with the H atom, and negative differential resistance behavior when modified with N or O. The analysis for the mechanism of the various properties has been presented with the highest occupied molecular orbital, lowest unoccupied molecular orbital and the transmission spectra. BibTeX: @article{Ma2015, title = {Controlling the electronic transport properties of the tetrapyrimidinyl molecule with atom modified sulfur bridge}, author = {Ma, Jie and Yang, Chuan-Lu and Wang, Mei-Shan and Ma, Xiao-Guang}, journal = {RSC Advances}, publisher = {The Royal Society of Chemistry}, volume = {5}, number = {14}, pages = {10675--10679}, year = {2015}, keywords = {area:molecular electronics}, area = {molecular electronics} doi = {10.1039/C4RA14163F}, }  Jiming Zheng, Xiaoqing Deng, Jianwei Zhao, Ping Guo, Chongfeng Guo, Zhaoyu Ren & Jintao Bai, Coupling site controlled spin transport through the graphene nanoribbon junction: A first principles investigation, Computational Materials Science, Vol. 99 pp. 203--208 (2015) Coupling site control,First-principles calculation,Graphene nanoribbons,Spintronics,area:graphene graphene Abstract: A new type of nano-junctions based on Zigzag graphene nanoribbons (ZGNRs) has been proposed and investigated by first-principles calculations. The results show that large spin polarization of currents would be achieved when the junctions adopted the configuration that two ZGNR leads coupled each other along one edge. By virtue of spatial separation of the two spin edge states, only one spin channel is opened in those junctions at certain energy range, and spin polarized currents will be produced under a low bias. No more efforts are required to change ZGNR from the antiferromagnetic (AFM) ground states to the ferromagnetic (FM) states. Specially, this feature is stable, by changing the width of ZGNRs, modifying the edge morphology, and varying dihedral angle between two ZGNRs, spin polarization of currents are still observed. Our findings indicate that this approach is simple and efficient for spintronics design. BibTeX: @article{Zheng2015, title = {Coupling site controlled spin transport through the graphene nanoribbon junction: A first principles investigation}, author = {Zheng, Jiming and Deng, Xiaoqing and Zhao, Jianwei and Guo, Ping and Guo, Chongfeng and Ren, Zhaoyu and Bai, Jintao}, journal = {Computational Materials Science}, volume = {99}, pages = {203--208}, year = {2015}, keywords = {Coupling site control,First-principles calculation,Graphene nanoribbons,Spintronics,area:graphene}, area = {graphene} doi = {10.1016/j.commatsci.2014.12.031}, }  Sumeet C. Pandey, Roy Meade & Gurtej S. Sandhu, Cu impurity in insulators and in metal-insulator-metal structures: Implications for resistance-switching random access memories, Journal of Applied Physics, Vol. 117(5), pp. 54504 (2015) AUGMENTED-WAVE METHOD,Copper,Density functional theory,Electric fields,Electrodes,INITIO MOLECULAR-DYNAMICS,Insulators,SEMICONDUCTORS,SIMULATION,STATES,area:interfaces,area:nvm,area:semi,metal-insulator interface,switching interfaces,nvm,semi Abstract: We present numerical results from atomistic simulations of Cu in SiO2 and Al2O3, with an emphasis on the thermodynamic, kinetic, and electronic properties. The calculated properties of Cu impurity at various concentrations (9.91E+20 cm-3 and 3.41E+22 cm-3) in bulk oxides are presented. The metal-insulator interfaces result in up to a 4 eV reduction in the formation energies relative to the crystalline bulk. Additionally, the importance of Cu-Cu interaction in lowering the chemical potential is introduced. These concepts are then discussed in the context of formation and stability of localized conductive paths in resistance-switching Random Access Memories (RRAM-M). The electronic density of states and non-equilibrium transmission through these localized paths are studied, confirming conduction by showing three orders of magnitude increase in the electron transmission. The dynamic behavior of the conductive paths is investigated with atomistic drift-diffusion calculations. Finally, the paper concludes with a molecular dynamics simulation of a RRAM-M cell that attempts to combine the aforementioned phenomena in one self-consistent model. BibTeX: @article{Pandey2015, title = {Cu impurity in insulators and in metal-insulator-metal structures: Implications for resistance-switching random access memories}, author = {Pandey, Sumeet C and Meade, Roy and Sandhu, Gurtej S}, journal = {Journal of Applied Physics}, volume = {117}, number = {5}, pages = {54504}, year = {2015}, keywords = {AUGMENTED-WAVE METHOD,Copper,Density functional theory,Electric fields,Electrodes,INITIO MOLECULAR-DYNAMICS,Insulators,SEMICONDUCTORS,SIMULATION,STATES,area:interfaces,area:nvm,area:semi,metal-insulator interface,switching}, area = {interfaces,nvm,semi} doi = {10.1063/1.4907578}, }  M.A. Mehrabova, H.R. Nuriyev, H.S. Orujov, A.M. Nazarov, R.M. Sadigov & V.N. Poladova, Defect formation energy for charge states and electrophysical properties of CdMnTe, Vol. 9450 pp. 94500Q (2015) area:materials materials Abstract: In this work the results of investigation of Cd1-xMnxTe (x=0.01, 0.03, 0.05) solid solutions synthesis and their thin films' obtaining technology have been represented. Epitaxial films of monocrystalline Cd1-xMnxTe semimagnetic semiconductors were obtained on mica substrate by MBC method. Lattice parameters and crystal structure of samples were defined with X-ray diffraction method. It has been studied the electrophysical parameters. Defect formation energy has been calculated for Cd1-xMnxTe semimagnetic semiconductors by Ab-initio method using Atomistix Toolkit program. We have studied the dependence of defect formation energy on supercell size for charged vacancy and interstitial defects in Cd1-xMnxTe thin films. BibTeX: @inproceedings{Mehrabova2015, title = {Defect formation energy for charge states and electrophysical properties of CdMnTe}, author = {Mehrabova, M A and Nuriyev, H R and Orujov, H S and Nazarov, A M and Sadigov, R M and Poladova, V N}, booktitle = {Proc. SPIE}, volume = {9450}, pages = {94500Q}, year = {2015}, keywords = {area:materials}, area = {materials} doi = {10.1117/12.2073343}, }  G. Berdiyorov, K. Harrabi, U. Mehmood, F.M. Peeters, N. Tabet, J. Zhang, I.A. Hussein & M.A. McLachlan, Derivatization and diffusive motion of molecular fullerenes: Ab initio and atomistic simulations, Journal of Applied Physics, Vol. 118(2), pp. 025101 (2015) Diffusion,Ethanol,Fullerenes,Solvents,Transport properties,area:molecular electronics molecular electronics Abstract: Using first principles density functional theory in combination with the nonequilibrium Green's function formalism, we study the effect of derivatization on the electronic and transport properties of C60backslashrbackslashnfullerene. As a typical example, we consider [6,6]-phenyl-C61-butyric acid methyl ester (PCBM), which forms one of the most efficient organic photovoltaic materials in combination with electron donating polymers. Extra peaks are observed in the density of states (DOS) due to the formation of new electronic states localized at/near the attached molecule. Despite such peculiar behavior in the DOS of an isolated molecule, derivatization does not have a pronounced effect on the electronic transport properties of the fullerene molecular junctions. Both C60 and PCBM show the same response to finite voltage biasing with new features in the transmission spectrum due to voltage induced delocalization of some electronic states. We also study the diffusive motion of molecular fullerenes in ethanolbackslashrbackslashnsolvent and inside poly(3-hexylthiophene) lamella using reactive molecular dynamics simulations. We found that the mobility of the fullerene reduces considerably due to derivatization; the diffusion coefficient of C60 is an order of magnitude larger than the one for PCBM. BibTeX: @article{Berdiyorov2015b, title = {Derivatization and diffusive motion of molecular fullerenes: Ab initio and atomistic simulations}, author = {Berdiyorov, G. and Harrabi, K. and Mehmood, U. and Peeters, F. M. and Tabet, N. and Zhang, J. and Hussein, I. A. and McLachlan, M. A.}, journal = {Journal of Applied Physics}, volume = {118}, number = {2}, pages = {025101}, year = {2015}, keywords = {Diffusion,Ethanol,Fullerenes,Solvents,Transport properties,area:molecular electronics}, area = {molecular electronics} doi = {10.1063/1.4923352}, }  Zhi Yang, Yu-Long Ji, Guoqiang Lan, Li-Chun Xu, Xuguang Liu & Bingshe Xu, Design molecular rectifier and photodetector with all-boron fullerene, Solid State Communications, Vol. 217 pp. 38--42 (2015) C-60,CLUSTER,Cluster,DIMER,First-principles study,NEGATIVE DIFFERENTIAL RESISTANCE,PLANAR,Transport properties,area:molecular electronics molecular electronics Abstract: All-boron fullerene B40 is a highly stable molecule, which has been successfully synthesized in recent experiment. In this paper, with Au as two electrodes, the single-molecule device Au-B40-Au was investigated by using density functional theory and non-equilibrium Green's function method. The results show that the device can exhibit large rectification ratio and significant negative differential resistance. More importantly, the photocurrent of the device has different responses in the infrared, visible and ultraviolet regions. The excellent optoelectronic properties ensure that the device can be used as photodetector. BibTeX: @article{Yang2015c, title = {Design molecular rectifier and photodetector with all-boron fullerene}, author = {Yang, Zhi and Ji, Yu-Long and Lan, Guoqiang and Xu, Li-Chun and Liu, Xuguang and Xu, Bingshe}, journal = {Solid State Communications}, volume = {217}, pages = {38--42}, year = {2015}, keywords = {C-60,CLUSTER,Cluster,DIMER,First-principles study,NEGATIVE DIFFERENTIAL RESISTANCE,PLANAR,Transport properties,area:molecular electronics}, area = {molecular electronics} doi = {10.1016/j.ssc.2015.05.013}, }  Bo Jiang, Yan-Hong Zhou, Chang-Yong Chen & Ke-Qiu Chen, Designing multi-functional devices based on two benzene rings molecule modulated with Co and N atoms, Organic Electronics, Vol. 23 pp. 133--137 (2015) Multi-functional device,Phenyl-ring,Spins transp,area:molecular electronics molecular electronics Abstract: We investigate the electronic transport properties in molecular devices consisting of two phenyl-rings connected by Co and N atoms by using nonequilibrium Green's function method and density function theory. The molecule is coupled to two zigzag graphene nanoribbon electrodes. It is found that giant magnetoresistance effect exists in both the coplanar and the perpendicular conformations at low biases. And the total current decreases a lot, on order of 100, when the orientation of the phenyl ring changes from coplanar site to perpendicular site. This indicates a molecular switcher via conformational control. What's more, perfect dual spin-filtering effect and rectifying behavior can be realized by modulating the external magnetic field. So a multi-functional device is achieved in our designed molecular junction. Detailed explanations via transmission spectra, distribution of molecular projected self-consistent Hamiltonian states are given to the above useful phenomenon. BibTeX: @article{Jiang2015, title = {Designing multi-functional devices based on two benzene rings molecule modulated with Co and N atoms}, author = {Jiang, Bo and Zhou, Yan-Hong and Chen, Chang-Yong and Chen, Ke-Qiu}, journal = {Organic Electronics}, volume = {23}, pages = {133--137}, year = {2015}, keywords = {Multi-functional device,Phenyl-ring,Spins transp,area:molecular electronics}, area = {molecular electronics} doi = {10.1016/j.orgel.2015.04.015}, }  Benoy Anand, Mehmet Karakaya, Gyan Prakash, S. Siva Sankara Sai, Reji Philip, Paola Ayala, Anurag Srivastava, Ajay K. Sood, Apparao M. Rao & Ramakrishna Podila, Dopant-configuration controlled carrier scattering in graphene, RSC Adv., Vol. 5(73), pp. 59556--59563 (2015) area:graphene graphene Abstract: Controlling optical and electronic properties of graphene via substitutional doping is central to many fascinating applications. Doping graphene with boron (B) or nitrogen (N) has led to p- or n-type graphene; however, the electron mobility in doped-graphene is severely compromised due to increased electron-defect scattering. Here, we demonstrate through Raman spectroscopy, nonlinear optical and ultrafast spectroscopy, and density functional theory that the graphitic dopant configuration is stable in graphene and does not significantly alter electron–electron or electron–phonon scattering, that is otherwise present in doped graphene, by preserving the crystal coherence length (La). BibTeX: @article{Anand2015, title = {Dopant-configuration controlled carrier scattering in graphene}, author = {Anand, Benoy and Karakaya, Mehmet and Prakash, Gyan and Sankara Sai, S. Siva and Philip, Reji and Ayala, Paola and Srivastava, Anurag and Sood, Ajay K. and Rao, Apparao M. and Podila, Ramakrishna}, journal = {RSC Adv.}, publisher = {Royal Society of Chemistry}, volume = {5}, number = {73}, pages = {59556--59563}, year = {2015}, keywords = {area:graphene}, area = {graphene} doi = {10.1039/C5RA05338B}, }  G.R. Berdiyorov, Effect of lithium and sodium ion adsorption on the electronic transport properties of Ti3C2 MXene, Applied Surface Science, Vol. 359 pp. 153--157 (2015) DFT,Electronic transport,MXenes,area:2dmat 2dmat Abstract: MXenes are found to be promising electrode materials for energy storage applications. Recent theoretical and experimental studies indicate the possibility of using these novel low dimensional materials for metal-ion batteries. Herein, we use density-functional theory in combination with the nonequilibrium Green's function formalism to study the effect of lithium and sodium ion adsorption on the electronic transport properties of the MXene, Ti3C2. Oxygen, hydroxyl and fluorine terminated species are considered and the obtained results are compared with the ones for the pristine MXene. We found that the ion adsorption results in reduced electronic transport in the pristine MXene: depending on the type of the ions and the bias voltage, the current in the system can be reduced by more than 30%. On the other hand, transport properties of the oxygen terminated sample can be improved by the ion adsorption: for both types of ions the current in the system can be increased by more than a factor of 4. However, the electronic transport is less affected by the ions in fluorinated and hydroxylated samples. These two samples show enhanced electronic transport as compared to the pristine MXene. The obtained results are explained in terms of electron localization in the system. BibTeX: @article{Berdiyorov2015, title = {Effect of lithium and sodium ion adsorption on the electronic transport properties of Ti3C2 MXene}, author = {Berdiyorov, G.R.}, journal = {Applied Surface Science}, publisher = {Elsevier B.V.}, volume = {359}, pages = {153--157}, year = {2015}, keywords = {DFT,Electronic transport,MXenes,area:2dmat}, area = {2dmat} doi = {10.1016/j.apsusc.2015.10.050}, }  Qiang Fu, Luis César Colmenares Rausseo, Umberto Martinez, Paul Inge Dahl, Juan Maria García Lastra, Per Erik Vullum, Ingeborg Helene Svenum & Tejs Vegge, Effect of Sb Segregation on Conductance and Catalytic Activity at Pt/Sb-Doped SnO2 Interface: A Synergetic Computational and Experimental Study, ACS Applied Materials and Interfaces, Vol. 7(50), pp. 27782--27795 (2015) DENSITY-FUNCTIONAL THEORY,ELECTRICAL-CONDUCTIVITY,ELECTROCATALYTIC ACTIVITY,ELECTROLYTE FUEL-CELLS,OXYGEN REDUCTION,SUPPORT MATERIALS,SURFACE SEGREGATION,THERMODYNAMIC ANALYSIS,TOTAL-ENERGY CALCULATIONS,WAVE BASIS-SET,area:battery,area:interfaces,catalyst,electronic transport,fuel cell,interface,segregation battery,interfaces Abstract: Antimony-doped tin dioxide (ATO) is considered a promising support material for Pt-based fuel cell cathodes, displaying enhanced stability over carbon-based supports. In this work, the effect of Sb segregation on the conductance and catalytic activity at Pt/ATO interface was investigated through a combined computational and experimental study. It was found that Sb-dopant atoms prefer to segregate toward the ATO/Pt interface. The deposited Pt catalysts, interestingly, not only promote Sb segregation, but also suppress the occurrence of Sb3+ species, a charge carrier neutralizer at the interface. The conductivity of ATO was found to increase, to a magnitude close to that of activated carbon, with an increment of Sb concentration before reaching a saturation point around 10%, and then decrease, indicating that Sb enrichment at the ATO surface may not always favor an increment of the electric current. In addition, the calculation results show that the presence of Sb dopants in ATO has little effect on the catalytic activity of deposited three-layer Pt toward the oxygen reduction reaction, although subsequent alloying of Pt and Sb could lower the corresponding catalytic activity. These findings help to support future applications of ATO/Pt-based materials as possible cathodes for proton exchange membrane fuel cell applications with enhanced durability under practical applications. BibTeX: @article{Fu2015, title = {Effect of Sb Segregation on Conductance and Catalytic Activity at Pt/Sb-Doped SnO2 Interface: A Synergetic Computational and Experimental Study}, author = {Fu, Qiang and Colmenares Rausseo, Luis César and Martinez, Umberto and Dahl, Paul Inge and García Lastra, Juan Maria and Vullum, Per Erik and Svenum, Ingeborg Helene and Vegge, Tejs}, journal = {ACS Applied Materials and Interfaces}, volume = {7}, number = {50}, pages = {27782--27795}, year = {2015}, keywords = {DENSITY-FUNCTIONAL THEORY,ELECTRICAL-CONDUCTIVITY,ELECTROCATALYTIC ACTIVITY,ELECTROLYTE FUEL-CELLS,OXYGEN REDUCTION,SUPPORT MATERIALS,SURFACE SEGREGATION,THERMODYNAMIC ANALYSIS,TOTAL-ENERGY CALCULATIONS,WAVE BASIS-SET,area:battery,area:interfaces,catalyst,electronic transport,fuel cell,interface,segregation}, area = {battery,interfaces} doi = {10.1021/acsami.5b08966}, }  G.R. Berdiyorov, Effect of surface functionalization on the electronic transport properties of Ti 3 C 2 MXene, EPL (Europhysics Letters), Vol. 111(6), pp. 67002 (2015) 2-DIMENSIONAL TITANIUM CARBIDE,ANODE,HIGH VOLUMETRIC CAPACITANCE,INTERCALATION,LITHIUM-ION BATTERIES,TRANSITION-METAL CARBIDES,area:2dmat 2dmat Abstract: The effects of surface functionalization on the electronic transport properties of the MXene compound Ti3C2 are studied using density-functional theory in combination with the nonequilibrium Green's function formalism. Fluorinated, oxidized and hydroxylated surfaces are considered and the obtained results are compared with the ones for the pristine MXene. It is found that the surface termination has a considerable impact on the electronic transport in MXene. For example, the fluorinated sample shows the largest transmission, whereas surface oxidation results in a considerable reduction of the electronic transmission. The current in the former sample can be up to 4 times larger for a given bias voltage as compared to the case of bare MXene. The increased transmission originates from the extended electronic states and smaller variations of the electrostatic potential profile. Our findings can be useful in designing MXene-based anode materials for energy storage applications, where enhanced electronic transport will be an asset. BibTeX: @article{Berdiyorov2015c, title = {Effect of surface functionalization on the electronic transport properties of Ti 3 C 2 MXene}, author = {Berdiyorov, G. R.}, journal = {EPL (Europhysics Letters)}, volume = {111}, number = {6}, pages = {67002}, year = {2015}, keywords = {2-DIMENSIONAL TITANIUM CARBIDE,ANODE,HIGH VOLUMETRIC CAPACITANCE,INTERCALATION,LITHIUM-ION BATTERIES,TRANSITION-METAL CARBIDES,area:2dmat}, area = {2dmat} doi = {10.1209/0295-5075/111/67002}, }  Xiaobo Li, Hui-Li Li, Haiqing Wan & Guanghui Zhou, Effects of amino-nitro side groups on electron device of oligo p-phenylenevinylene molecular between ZGNR electrodes, Organic Electronics, Vol. 19 pp. 26--33 (2015) NDR and spin-rectifying effects,OPV molecular device,ab initio calculations,area:molecular electronics molecular electronics Abstract: We study the electronic transport property for a molecular device of an oligo (p-phenylenevinylene) (OPV) molecule without or with different side groups between two zigzag-edged graphene nanoribbon (ZGNR) electrodes. By using ab initio calculations based on density-functional theory, the effects of negative differential resistance (NDR) and spin-rectifying in I-V characteristics are revealed and explained for the proposed molecular device. Our analysis indicates that the NDR behavior comes from the conduction orbital being suppressed under certain bias voltage, while the rectifying effect is because of the asymmetry distribution of the highest occupied molecular orbital or the lowest unoccupied molecular one as well as the corresponding coupling between the molecule and electrodes. Interestingly, the transport property of the device can be improved by introducing amino-nitro side groups to the OPV molecule. The NDR behavior can be much enhanced for molecule with amino side group, and the rectification can be improved for molecule with amino and nitro side groups, respectively. In particular, the NDR behavior of peak to valley ratio can be much enhanced and a molecular rectifier which offers rectification ratio of more than three orders of magnitude up to 2863 by adding NH2 and NO2 side groups to OPV molecule, respectively. BibTeX: @article{Li2015c, title = {Effects of amino-nitro side groups on electron device of oligo p-phenylenevinylene molecular between ZGNR electrodes}, author = {Li, Xiaobo and Li, Hui-Li and Wan, Haiqing and Zhou, Guanghui}, journal = {Organic Electronics}, volume = {19}, pages = {26--33}, year = {2015}, keywords = {NDR and spin-rectifying effects,OPV molecular device,ab initio calculations,area:molecular electronics}, area = {molecular electronics} doi = {10.1016/j.orgel.2015.01.006}, }  Anurag Srivastava, Vikash Sharma, Kamalpreet Kaur, Md. Shahzad Khan, Rajeev Ahuja & V.K. Rao, Electron transport properties of a single-walled carbon nanotube in the presence of hydrogen cyanide: first-principles analysis, Journal of Molecular Modeling, Vol. 21(7), pp. 1--7 (2015) Band structure,Conductance,First principles,HCN,SWCNT,Sensor,area:2dmat 2dmat Abstract: First-principles analysis based on density functional theory was performed to compute the electronic and transport properties of a single-walled carbon nanotube in the presence of hydrogen cyanide. A chiral (4,1) carbon nanotube was found to become less metallic as the number of hydrogen cyanide molecules nearby increased. When there were a sufficient number of hydrogen cyanide molecules close to the nanotube, it became semiconducting. This metallic to semiconducting transformation of the nanotube was verified by analyzing its conductance and current as a function of the number of molecules of hydrogen cyanide present. The conductivity of the carbon nanotube was very high when no hydrogen cyanide molecules were present, but decreased considerably when even just a single hydrogen cyanide molecule approached the surface of the nanotube. BibTeX: @article{Srivastava2015e, title = {Electron transport properties of a single-walled carbon nanotube in the presence of hydrogen cyanide: first-principles analysis}, author = {Srivastava, Anurag and Sharma, Vikash and Kaur, Kamalpreet and Khan, Md. Shahzad and Ahuja, Rajeev and Rao, V K}, journal = {Journal of Molecular Modeling}, volume = {21}, number = {7}, pages = {1--7}, year = {2015}, keywords = {Band structure,Conductance,First principles,HCN,SWCNT,Sensor,area:2dmat}, area = {2dmat} doi = {10.1007/s00894-015-2720-3}, }  Sarah L.T. Jones, Alfonso Sanchez-Soares, John J. Plombon, Ananth P. Kaushik, Roger E. Nagle, James S. Clarke & James C. Greer, Electron transport properties of sub-3-nm diameter copper nanowires, Physical Review B - Condensed Matter and Materials Physics, Vol. 92(11), pp. 115413 (2015) area:nanowires,industrial nanowires Abstract: Density functional theory and density functional tight binding are applied to model electron transport in copper nanowires of approximately 1- and 3-nm diameters with varying crystal orientation and surface termination. The copper nanowires studied are found to be metallic irrespective of diameter, crystal orientation, and/or surface termination. Electron transmission is highly dependent on crystal orientation and surface termination. Nanowires oriented along the [110] crystallographic axis consistently exhibit the highest electron transmission while surface oxidized nanowires show significantly reduced electron transmission compared to unterminated nanowires. Transmission per unit area is calculated in each case; for a given crystal orientation we find that this value decreases with diameter for unterminated nanowires but is largely unaffected by diameter in surface oxidized nanowires for the size regime considered. Transmission pathway plots show that transmission is larger at the surface of unterminated nanowires than inside the nanowire and that transmission at the nanowire surface is significantly reduced by surface oxidation. Finally, we present a simple model which explains the transport per unit area dependence on diameter based on transmission pathways results. BibTeX: @article{Jones2015, title = {Electron transport properties of sub-3-nm diameter copper nanowires}, author = {Jones, Sarah L T and Sanchez-Soares, Alfonso and Plombon, John J. and Kaushik, Ananth P. and Nagle, Roger E. and Clarke, James S. and Greer, James C.}, journal = {Physical Review B - Condensed Matter and Materials Physics}, volume = {92}, number = {11}, pages = {115413}, year = {2015}, keywords = {area:nanowires,industrial}, area = {nanowires} doi = {10.1103/PhysRevB.92.115413}, }  Qingyun Wu, Lei Shen, Ming Yang, Yongqing Cai, Zhigao Huang & Yuan Ping Feng, Electronic and transport properties of phosphorene nanoribbons, Physical Review B - Condensed Matter and Materials Physics, Vol. 92(3), pp. 035436 (2015) BAND,CRYSTALS,LAYER BLACK PHOSPHORUS,MOBILITY,MOS2 NANORIBBONS,SEMICONDUCTOR,STRAIN,TRANSISTORS,area:2dmat 2dmat Abstract: By combining density functional theory and nonequilibrium Green's function, we study the electronic and transport properties of monolayer black phosphorus nanoribbons (PNRs). First, we investigate the band gap of PNRs and its modulation by the ribbon width and an external transverse electric field. Our calculations indicate a giant Stark effect in PNRs, which can switch on transport channels of semiconducting PNRs under low bias, inducing an insulator-metal transition. Next, we study the transport channels in PNRs via the calculations of the current density and local electron transmission pathway. In contrast to graphene and MoS2 nanoribbons, the carrier transport channels under low bias are mainly located in the interior of both armchair and zigzag PNRs, and immune to a small amount of edge defects. Last, a device of the PNR-based dual-gate field-effect transistor, with high on/off ratio of 10(3), is proposed based on the giant electric-field tuning effect. BibTeX: @article{Wu2015c, title = {Electronic and transport properties of phosphorene nanoribbons}, author = {Wu, Qingyun and Shen, Lei and Yang, Ming and Cai, Yongqing and Huang, Zhigao and Feng, Yuan Ping}, journal = {Physical Review B - Condensed Matter and Materials Physics}, volume = {92}, number = {3}, pages = {035436}, year = {2015}, keywords = {BAND,CRYSTALS,LAYER BLACK PHOSPHORUS,MOBILITY,MOS2 NANORIBBONS,SEMICONDUCTOR,STRAIN,TRANSISTORS,area:2dmat}, area = {2dmat} doi = {10.1103/PhysRevB.92.035436}, }  Yuan Peng-Fei Yu Zhuo-Liang Tao Bin-Kai Hou Sen-Yao Ye Cong Zhang Zhen-Hua Tian Wen, Electronic properties of doped hexagonal graphene, Acta Physica Sinica, Vol. 64(4), pp. 46102 (2015) area:graphene,area:molecular electronics,electronic tr,heteroatom doping,hexagonal graphene graphene,molecular electronics Abstract: Zigzag- and armchair-edged hexagonal graphenes are sandwiched between two Au electrodes to construct molecular nanodevices, and the effects of the orderly and locally doped with B, N, and BN for such graphene nanoflakes are considered, respectively. Based on the first-principles method, the electronic transport properties of these devices are investigated systematically. Our calculated results show that the using of B and BN to dope armchair-edged hexagonal graphenes can modulate the electronic transport properties significantly. Intrinsic and doped zigzag-hexagonal graphenes presents a semiconductoring behavior, and when it is doped with N and BN, there appears a negative differential resistance (NDR) phenomenon, especially for N-doping, and a very obvious NDR can be observed in zigzag-edged hexagonal grapheme: this might be important for developing molecular switches. The underlying causes for these findings are clearly elucidated by the transmission features and the doping-induced changes in electronic properties of a hexagonal graphene. BibTeX: @article{Tian2015, title = {Electronic properties of doped hexagonal graphene}, author = {Tian Wen, Yuan Peng-Fei Yu Zhuo-Liang Tao Bin-Kai Hou Sen-Yao Ye Cong Zhang Zhen-Hua}, journal = {Acta Physica Sinica}, publisher = {Acta Physica Sinica}, volume = {64}, number = {4}, pages = {46102}, year = {2015}, keywords = {area:graphene,area:molecular electronics,electronic tr,heteroatom doping,hexagonal graphene}, area = {graphene,molecular electronics} doi = {10.7498/aps.64.046102}, }  J. Liu, Z.H. Zhang, X.Q. Deng, Z.Q. Fan & G.P. Tang, Electronic structures and transport properties of armchair graphene nanoribbons by ordered doping, Organic Electronics, Vol. 18 pp. 135--142 (2015) Electronic structure,Graphene nanoribbons,Orderly doping,Transport properties,area:graphene graphene Abstract: Based on the first-principles method, the electronic structures and transport properties of armchair graphene nanoribbons (AGNRs) with ordered doping of B atoms or N atoms or BN molecules are studied systematically. It shows that the AGNRs may be a metal or a semiconductor depending on B or N atom-doping positions, and the calculated atom-projected density of states (atom-PDOS) indicates that B or N impurity atoms can induce the new lowest conduction band (LCB) or the highest valence band (HVB). More interestingly, as compared with the intrinsic AGNR device, the current in the B- or N-doped AGNR device with the most energetically favorable state is extremely small, completely different from a macroscopic Si semiconductor with p-type or n-type doping, which always leads to a significant increase in current. Also shown is that the doping with BN molecules generally increases the bandgap of the AGNR regardless of the doping position, but the size of these bandgaps depends on the doping positions. The current in the BN-doped AGNR device is also decreased greatly in comparison with that for the intrinsic AGNR device. BibTeX: @article{Liu2015b, title = {Electronic structures and transport properties of armchair graphene nanoribbons by ordered doping}, author = {Liu, J and Zhang, Z H and Deng, X Q and Fan, Z Q and Tang, G P}, journal = {Organic Electronics}, volume = {18}, pages = {135--142}, year = {2015}, keywords = {Electronic structure,Graphene nanoribbons,Orderly doping,Transport properties,area:graphene}, area = {graphene} doi = {10.1016/j.orgel.2015.01.013}, }  Jun Ouyang, Mengqiu Long, Dan Zhang, Xiaojiao Zhang, Jun He & Yongli Gao, Electronic structures and transport properties of zigzag BNC nanoribbons with different combinations of BN and graphene nanoribbons, Computational Condensed Matter, Vol. 4 pp. 40--45 (2015) Boron nitride nanoribbon,Electronic structure,Graphene nanoribbon,Transport property,Zigzag boron-nitrogen-carbon nanoribbon,area:2dmat 2dmat Abstract: Using the density functional theory (DFT) and the nonequilibrium Green's function (NEGF) method, we study the electronic structures and transport properties of zigzag boron-nitrogen-carbon nanoribbons (BNCNRs), which are constructed by the substructures of the B-N nanoribbons (BNNRs) and graphene nanoribbons (GNRs). The different position relationships (center or edge) of the BNNRs and GNRs, and the different edge patterns of the BNCNRs have been considered systematically. We found the electronic structures and transport properties of BNCNRs are significantly affected. The metallic and semiconductive properties of the BNCNRs can be modulated by the different combinations of the BNNRs and GNRs. And our results suggest BNCNRs would have potential applications in graphene-based nano-devices. BibTeX: @article{Ouyang2015, title = {Electronic structures and transport properties of zigzag BNC nanoribbons with different combinations of BN and graphene nanoribbons}, author = {Ouyang, Jun and Long, Mengqiu and Zhang, Dan and Zhang, Xiaojiao and He, Jun and Gao, Yongli}, journal = {Computational Condensed Matter}, publisher = {Elsevier Ltd}, volume = {4}, pages = {40--45}, year = {2015}, keywords = {Boron nitride nanoribbon,Electronic structure,Graphene nanoribbon,Transport property,Zigzag boron-nitrogen-carbon nanoribbon,area:2dmat}, area = {2dmat} doi = {10.1016/j.cocom.2015.08.001}, }  Anurag Srivastava, Chetan Bhat, Sumit Kumar Jain, Pankaj Kumar Mishra & Ranjeet Brajpuriya, Electronic transport properties of BN sheet on adsorption of ammonia (NH3) gas, Journal of Molecular Modeling, Vol. 21(3), pp. 1--8 (2015) AB-INITIO,Ab initio,Ammonia,Band structure,Boron,GENERALIZED GRADIENT APPROXIMATION,GRAPHENE,I-V,NANOTUBES,Nitrite,SENSORS,Sensor,area:2dmat 2dmat Abstract: We report the detection of ammonia gas through electronic and transport properties analysis of boron nitride sheet. The density functional theory (DFT) based ab initio approach has been used to calculate the electronic and transport properties of BN sheet in presence of ammonia gas. Analysis confirms that the band gap of the sheet increases due to presence of ammonia. Out of different positions, the bridge site is the most favorable position for adsorption of ammonia and the mechanism of interaction falls between weak electrostatic interaction and chemisorption. On relaxation, change in the bond angles of the ammonia molecule in various configurations has been reported with the distance between NH3 and the sheet. An increase in the transmission of electrons has been observed on increasing the bias voltage and I-V relationship. This confirms that, the current increases on applying the bias when ammonia is introduced while a very small current flows for pure BN sheet. BibTeX: @article{Srivastava2015, title = {Electronic transport properties of BN sheet on adsorption of ammonia (NH3) gas}, author = {Srivastava, Anurag and Bhat, Chetan and Jain, Sumit Kumar and Mishra, Pankaj Kumar and Brajpuriya, Ranjeet}, journal = {Journal of Molecular Modeling}, volume = {21}, number = {3}, pages = {1--8}, year = {2015}, keywords = {AB-INITIO,Ab initio,Ammonia,Band structure,Boron,GENERALIZED GRADIENT APPROXIMATION,GRAPHENE,I-V,NANOTUBES,Nitrite,SENSORS,Sensor,area:2dmat}, area = {2dmat} doi = {10.1007/s00894-015-2595-3}, }  Yukihito Matsuura, Electronic transport properties of diamondoids, Computational and Theoretical Chemistry, Vol. 1074 pp. 131--135 (2015) DFT,Diamondoid,Doping,Electronic transport properties,NEGF,area:molecular electronics molecular electronics Abstract: The electronic transport properties of diamantanes as a model of diamondoids (nanodiamonds) were studied by first-principles calculations. For this purpose, diamantane with thiol group was sandwiched between gold electrodes. Additionally, the effect of substitution of equatorial tertiary carbons on conductance was examined in detail. The conductance of boron- and phosphorus-substituted diamantanes was nearly the same as that of non-substituted diamantane, whereas the conductance of nitrogen-doped diamantane was higher. This is due to the fact that the nitrogen-substitution increases the transmittance at the Fermi level by the overlap of nitrogen 2p and sulfur 3s orbitals. Furthermore, the heteroatom-substituted diamantanes exhibited current rectification to a certain degree. BibTeX: @article{Matsuura2015a, title = {Electronic transport properties of diamondoids}, author = {Matsuura, Yukihito}, journal = {Computational and Theoretical Chemistry}, publisher = {Elsevier B.V.}, volume = {1074}, pages = {131--135}, year = {2015}, keywords = {DFT,Diamondoid,Doping,Electronic transport properties,NEGF,area:molecular electronics}, area = {molecular electronics} doi = {10.1016/j.comptc.2015.10.025}, }  Yukihito Matsuura, Electronic transport properties of linear homocatenated indium chains, Theoretical Chemistry Accounts, Vol. 134(5), pp. 1--6 (2015) DFT,Indium chain,Molecular conduction,NEGF,area:molecular electronics molecular electronics Abstract: The electronic transport properties of linear homocatenated indium chain were estimated through first-principle calculations. Long chains comprising four or five indium atoms exhibited a large transmission peak at the Fermi level, which enhanced their conductance. This peak was caused by enhanced -conjugation in the indium main chain. Due to σ-conjugation, the conductance did not monotonously attenuate under tunneling upon extension of molecular length. Therefore, homocatenation in indium chains is a promising candidate for molecular conduction. BibTeX: @article{Matsuura2015, title = {Electronic transport properties of linear homocatenated indium chains}, author = {Matsuura, Yukihito}, journal = {Theoretical Chemistry Accounts}, volume = {134}, number = {5}, pages = {1--6}, year = {2015}, keywords = {DFT,Indium chain,Molecular conduction,NEGF,area:molecular electronics}, area = {molecular electronics} doi = {10.1007/s00214-015-1669-8}, }  Yi Zhou, JiChen Dong & Hui Li, Electronic transport property of in-plane heterostructures constructed by MoS2 and WS2 nanoribbons, RSC Adv., Vol. 5 pp. 66852--66860 (2015) BILAYER GRAPHENE,DICHALCOGENIDES,GATE DIELECTRICS,LAYERED MATERIALS,MOBILITY,PERFORMANCE,ROOM-TEMPERATURE,SCALE EPITAXIAL GRAPHENE,TRANSISTORS,TRANSITION,area:2dmat,area:tmd 2dmat,tmd Abstract: A new and simple kind of in-plane heterostructure is constructed by MoS2 nanoribbons (MoS2NRs) and WS2 nanoribbons (WS2NRs) arranged both perpendicularly and in parallel. The electronic transport properties of two-probe devices with these heterostructures are investigated by first-principle density functional theory and non-equilibrium Green function. The results indicate that for all these heterostructures, with the number of WS2NR unit cell increasing, the bandgap decreases slightly and the negative differential resistance (NDR) effect can be tuned. Especially for the case with W atoms doping on the edge, it not only displays a notable NDR effect but also has a high current peak under low bias, which indicates that it shows a better performance applied as a logic transistor. This study may provide a new path for the creation of the novel nanoelectronic devices with good performance. BibTeX: @article{Zhou2015b, title = {Electronic transport property of in-plane heterostructures constructed by MoS2 and WS2 nanoribbons}, author = {Zhou, Yi and Dong, JiChen and Li, Hui}, journal = {RSC Adv.}, publisher = {Royal Society of Chemistry}, volume = {5}, pages = {66852--66860}, year = {2015}, keywords = {BILAYER GRAPHENE,DICHALCOGENIDES,GATE DIELECTRICS,LAYERED MATERIALS,MOBILITY,PERFORMANCE,ROOM-TEMPERATURE,SCALE EPITAXIAL GRAPHENE,TRANSISTORS,TRANSITION,area:2dmat,area:tmd}, area = {2dmat,tmd} doi = {10.1039/C5RA14507D}, }  Yuehua Xu, Jun Dai & Xiao Cheng Zeng, Electron-Transport Properties of Few-Layer Black Phosphorus, The Journal of Physical Chemistry Letters, Vol. 6(11), pp. 1996--2002 (2015) area:2dmat,interlayer interaction,t,two-probe configuration 2dmat Abstract: We perform the first-principles computational study of the effect of number of stacking layers and stacking style of the few-layer black phosphorus (BPs) on the electronic properties, including transport gap, current-voltage (i-v) relation, and differential conductance. Our computation is based on the nonequilibrium Green's function approach combined with density functional theory calculations. Specifically, we compute electron-transport properties of monolayer BP, bilayer BP, and trilayer BP as well as bilayer BPs with AB-, AA-, or AC-stacking. We find that the stacking number has greater influence on the transport gap than the stacking type. Conversely, the stacking type has greater influence on i-v curve and differential conductance than on the transport gap. This study offers useful guidance for determining the number of stacking layers and the stacking style of few-layer BP sheets in future experimental measurements and for potential applications in nanoelectronic devices. BibTeX: @article{Xu2015, title = {Electron-Transport Properties of Few-Layer Black Phosphorus}, author = {Xu, Yuehua and Dai, Jun and Zeng, Xiao Cheng}, journal = {The Journal of Physical Chemistry Letters}, volume = {6}, number = {11}, pages = {1996--2002}, year = {2015}, keywords = {area:2dmat,interlayer interaction,t,two-probe configuration}, area = {2dmat} doi = {10.1021/acs.jpclett.5b00510}, }  Mamikon Gulian, Gurgen Melkonyan & Armen Gulian, Engineering room-temperature superconductors via ab-initio calculations, Physics Procedia: Proceedings of the 25th International Cryogenic Engineering Conference and International Cryogenic Materials Conference 2014, Vol. 67 pp. 963--969 (2015) area:materials,phonons,superconductivity materials Abstract: The BCS, or bosonic model of superconductivity, as Little and Ginzburg have first argued, can bring in superconductivity at room temperatures in case of high-enough frequency of bosonic mode. It was further elucidated by Kirzhnits et al., that the condition for existence of high-temperature superconductivity is closely related with negative values of the real part of dielectric function at finite values of the reciprocal lattice vectors. In view of these findings, the task is to calculate the dielectric function for real materials. Then the poles of this function will indicate the existence of bosonic excitations which can serve as a "glue" for Cooper pairing, and if the frequency is high enough, and the dielectric matrix is simultaneously negative, this material is a good candidate for very high-Tc superconductivity. Thus, our approach is to elaborate a methodology of ab-initio calculation of the dielectric function of various materials, and then point out appropriate candidates. We used the powerful codes (TDDF with the DP package in conjunction with ABINIT) for computing dielectric responses at finite values of the wave vectors in the reciprocal lattice space. Though our report is concerned with the particular problem of superconductivity, the application range of the data processing methodology is much wider. The ability to compute dielectric function of existing and still non-existing (though being predicted!) materials will have many more repercussions not only in fundamental sciences but also in technology and industry. BibTeX: @article{Gulian2015, title = {Engineering room-temperature superconductors via ab-initio calculations}, author = {Gulian, Mamikon and Melkonyan, Gurgen and Gulian, Armen}, journal = {Physics Procedia: Proceedings of the 25th International Cryogenic Engineering Conference and International Cryogenic Materials Conference 2014}, volume = {67}, pages = {963--969}, year = {2015}, keywords = {area:materials,phonons,superconductivity}, area = {materials} doi = {10.1016/j.phpro.2015.06.163}, }  Y.S. Liu, W.Q. Zhou, J.F. Feng & X.F. Wang, Enhanced spin thermoelectric effects in BN-embedded zigzag graphene nanoribbons, Chemical Physics Letters, Vol. 625 pp. 14--19 (2015) area:graphene,area:spintronics,nanoribbon graphene,spintronics Abstract: Spin thermoelectric effects in BN-embedded zigzag graphene nanoribbons (ZGNRs) are studied by a first-principles method. The multiple spin-up (spin-down) quasi-bound states below (above) the Fermi level can be introduced by the BN bonded pairs, leading to the dip structures in the transmission spectra. We further find that the spin thermoelectric effect at the Fermi level is obviously stronger than the corresponding charge thermoelectric effect. As the more BN bonded pairs are gradually doped from the edge to middle regions, the spin thermoelectric figure of merit (FOM) can be improved up to ten times than the charge thermoelectric FOM. A pure spin current can also be achieved in the BN-embedded ZGNRs under an external thermal bias. BibTeX: @article{Liu2015c, title = {Enhanced spin thermoelectric effects in BN-embedded zigzag graphene nanoribbons}, author = {Liu, Y S and Zhou, W Q and Feng, J F and Wang, X F}, journal = {Chemical Physics Letters}, volume = {625}, pages = {14--19}, year = {2015}, keywords = {area:graphene,area:spintronics,nanoribbon}, area = {graphene,spintronics} doi = {10.1016/j.cplett.2015.01.014}, }  Jia Zhu, W.J. Chen, G.H. Zhang & Yue Zheng, Exponential size-dependent tunability of strain on the transport behavior in ZnO tunnel junctions: an ab initio study, Phys. Chem. Chem. Phys., Vol. 17 pp. 25583--25592 (2015) area:spintronics spintronics Abstract: It is an interesting issue if the transport behavior of a piezoelectric tunnel junction is sensitive to external strain or stress, and it implies a prospect for developing novel mechanical sensors, transducers, piezotronic devices, etc. Many studies paid attention to this issue, yet how the strain and stress tunable transport behavior of a tunnel junction depends on the barrier thickness is still rarely known. Using the first principles calculations, we investigate the size-dependent and strain-tunable transport behavior in the tunnel junctions. It was confirmed that external strain has strong control over the transport properties of ZnO tunnel junctions, with several times amplification of tunnel conductance obtained by strain reversal. More importantly, the conductance amplification by strain reversal exponentially changes with the barrier thickness, indicating the size-dependent strain tunability of the transport behavior. The electrostatic quantities (i.e., built-in field, depolarization field, polarization, interfacial dipoles and potential barrier) and the transport properties of tunnel junctions were comprehensively analyzed to reveal the relationships between these quantities and their size dependence. The exponential size-dependence of strain tunable transport behavior in ZnO tunnel junctions is attributed to the linear change in the potential barrier with the barrier thickness. Our simulations provide an insight of how to maximize the strain tunability of transport behavior of piezoelectric tunnel junctions by thickness design and strain engineering. BibTeX: @article{Zhu2015b, title = {Exponential size-dependent tunability of strain on the transport behavior in ZnO tunnel junctions: an ab initio study}, author = {Zhu, Jia and Chen, W. J. and Zhang, G. H. and Zheng, Yue}, journal = {Phys. Chem. Chem. Phys.}, publisher = {Royal Society of Chemistry}, volume = {17}, pages = {25583--25592}, year = {2015}, keywords = {area:spintronics}, area = {spintronics} doi = {10.1039/C5CP03945B}, }  Bahniman Ghosh & Akash Gramin, First principle study of the effect of defects on performance of single-molecule pentacene field effect transistors, Journal of Theoretical and Applied Physics, Vol. 9(3), pp. 213--219 (2015) Density functional theory,Field effect transistors,Non-equilibrium green's function,Pentacene,area:molecular electronics molecular electronics Abstract: In this work, we have performed first principle study on a single-molecule pentacene field effect transistor and studied various oxygen- and hydrogen-induced defects in the same device configuration. Further, we have investigated the effect of these defects on the various electronic transport properties of the device and compared them with those of the original device along with reporting the negative differential region window and the peak-to-valley ratio in different cases. For this purpose, we have applied the density functional theory in conjugation with non-equilibrium green's function (NEGF) formalism on a 14.11 Å pentacene device to obtain the I–V characteristics, conductance curves and transmission spectra in various device scenarios. BibTeX: @article{Ghosh2015a, title = {First principle study of the effect of defects on performance of single-molecule pentacene field effect transistors}, author = {Ghosh, Bahniman and Gramin, Akash}, journal = {Journal of Theoretical and Applied Physics}, publisher = {Springer Berlin Heidelberg}, volume = {9}, number = {3}, pages = {213--219}, year = {2015}, keywords = {Density functional theory,Field effect transistors,Non-equilibrium green's function,Pentacene,area:molecular electronics}, area = {molecular electronics} doi = {10.1007/s40094-015-0182-8}, }  Rong-Fang Zhang, E. Yang, Yi Li, Li-Xiang Lin & Qi-Dan Ling, First Principle Study on the Rectification of Molecular Junctions Based on the Thiol-ended Oligosilane, Chinese Journal of Structural Chemistry, Vol. 34(6), pp. 813--821 (2015) DENSITY,NANOSENSORS,SILICON NANOWIRE,area:molecular electronics,first principle,rectification,thiol-ended oligosilane molecular electronics Abstract: The electron transport properties of various molecular junctions based on the thiol-ended oligosilane are investigated through density functional theory combined with non-equilibrium Green's function formalism. Our calculations show that oligosilanes doped by the phenyl and -C10H6 groups demonstrate better rectifying effect and their rectification ratios are up to 15.41 and 65.13 for their molecular junctions. The current-voltage (I-V) curves of all the Au/modified oligosilane/Au systems in this work are illustrated by frontier molecular orbitals, transmission spectra and density of states under zero bias. And their rectifying behaviors are analyzed through transmission spectra. BibTeX: @article{Zhang2015a, title = {First Principle Study on the Rectification of Molecular Junctions Based on the Thiol-ended Oligosilane}, author = {Zhang, Rong-Fang and Yang, E and Li, Yi and Lin, Li-Xiang and Ling, Qi-Dan}, journal = {Chinese Journal of Structural Chemistry}, volume = {34}, number = {6}, pages = {813--821}, year = {2015}, keywords = {DENSITY,NANOSENSORS,SILICON NANOWIRE,area:molecular electronics,first principle,rectification,thiol-ended oligosilane}, area = {molecular electronics} doi = {10.14102/j.cnki.0254-5861.2011-0590}, }  S. Caliskan & F. Hazar, First principles study on the spin unrestricted electronic structure properties of transition metal doped InN nanoribbons, Superlattices and Microstructures, Vol. 84 pp. 170--180 (2015) Energy gap,First principles,InN nanoribbon,Spin,area:graphene,area:materials,area:spin graphene,materials,spin Abstract: In the present study, first principles calculations were carried out to reveal the spin unrestricted electronic structure behavior of both pure and transition metal (TM) atom (V and Co) doped InN nanoribbons (InN-NRs). The influence of a substitutionally doped TM atom on the electronic structure nature was examined. The role of a TM dopant together with its location, governing the characteristic of spin dependent electronic property of a doped InN-NR, was addressed. The relevant properties were extracted through Hubbard correction for In-d, N-p and TM-d states. We observed that a single TM dopant diminished the spin dependent energy gap and can result in a significant induced magnetic moment in an InN-NR system. It was exposed that TM dopants can play an essential role in the spin unrestricted electronic behavior and spin polarization, which can be tuned through a V or Co atom at a certain position. BibTeX: @article{Caliskan2015, title = {First principles study on the spin unrestricted electronic structure properties of transition metal doped InN nanoribbons}, author = {Caliskan, S and Hazar, F}, journal = {Superlattices and Microstructures}, volume = {84}, pages = {170--180}, year = {2015}, keywords = {Energy gap,First principles,InN nanoribbon,Spin,area:graphene,area:materials,area:spin}, area = {graphene,materials,spin} doi = {10.1016/j.spmi.2015.05.004}, }  Anurag Srivastava & R. Chandiramouli, First-principles insights on electron transport in V2O5 nanostructures, Materials Science and Engineering: B, Vol. 201 pp. 45--50 (2015) Molecular device,Nanostructures,Pathways,Transmission,Vanadium oxide,area:semi semi Abstract: The present report is on the electron transport properties of V2O5 nanostructures, investigated using density functional theory. As the band structure of V2O5 exhibits semiconducting nature, the V2O5 nanostructures are designed as molecular device and the transport properties are studied. The density of electrons is found to be more in the oxygen sites than in vanadium sites. The device density of states shows that the density of electrons in the energy intervals depends on the applied bias voltage. The transmission spectrum gives the insight on the transport property of V2O5 molecular device. The bias voltage drives the electrons across V2O5 scattering region, where the transmission along V2O5 molecular device mainly depends on the bias voltage. The findings of the present work give insights to fine-tune the transport property of V2O5 molecular device upon varying the bias voltage. BibTeX: @article{Srivastava2015c, title = {First-principles insights on electron transport in V2O5 nanostructures}, author = {Srivastava, Anurag and Chandiramouli, R.}, journal = {Materials Science and Engineering: B}, publisher = {Elsevier B.V.}, volume = {201}, pages = {45--50}, year = {2015}, keywords = {Molecular device,Nanostructures,Pathways,Transmission,Vanadium oxide,area:semi}, area = {semi} doi = {10.1016/j.mseb.2015.08.001}, }  Hannah L. McFarland, Towfiq Ahmed, Jian Xin Zhu, Alexander V. Balatsky & Jason T. Haraldsen, First-Principles Investigation of Nanopore Sequencing Using Variable Voltage Bias on Graphene-Based Nanoribbons, Journal of Physical Chemistry Letters, Vol. 6(13), pp. 2616--2621 (2015) DNA/RNA sequencing,area:graphene,density functional theory,nanopore-based technology,nucleobase identification,transmission current graphene Abstract: In this study, we examine the mechanism of nanopore-based DNA sequencing using a voltage bias across a graphene nanoribbon. Using density function theory and a nonequilibrium Green's function approach, we determine the transmission spectra and current profile for adenine, guanine, cytosine, thymine, and uracil as a function of bias voltage in an energy minimized configuration. Utilizing the transmission current, we provide a general methodology for the development of a three nanopore graphene-based device that can be used to distinguish between the various nucleobases for DNA/RNA sequencing. From our analysis, we deduce that it is possible to use different transverse currents across a multinanopore device to differentiate between nucleobases using various voltages of 0.5, 1.3, and 1.6 V. Overall, our goal is to improve nanopore design to further DNA/RNA nucleobase sequencing and biomolecule identification techniques. BibTeX: @article{McFarland2015, title = {First-Principles Investigation of Nanopore Sequencing Using Variable Voltage Bias on Graphene-Based Nanoribbons}, author = {McFarland, Hannah L. and Ahmed, Towfiq and Zhu, Jian Xin and Balatsky, Alexander V. and Haraldsen, Jason T.}, journal = {Journal of Physical Chemistry Letters}, volume = {6}, number = {13}, pages = {2616--2621}, year = {2015}, keywords = {DNA/RNA sequencing,area:graphene,density functional theory,nanopore-based technology,nucleobase identification,transmission current}, area = {graphene} doi = {10.1021/acs.jpclett.5b01014}, }  Mudassir M. Husain & Maneesh Kumar, First-Principles Modeling of the Smallest Molecular Single Electron Transistor, Journal of Atomic, Molecular, Condensate and Nano Physics, Vol. 2(1), pp. 33--39 (2015) Charge stability diagram,Coulomb blockade,Ethyne,Incoherent transport,Quantum tunneling,Single electron transistor,area:molecular electronics molecular electronics Abstract: Using first-principles method the charging energy has been calculated; of the smallest single electron transistor (SET) consisting of only two carbon atoms while operating in coulumb blockade regime. The ethyne (C2H2) molecule is acting like a quantum dot (with discrete energy levels) and is weakly coupled to the gold electrodes (continuum). The quantum effects are significant and the conduction of current takes place through incoherent method via electron tunneling. The electronic levels of the molecule determine the electron transport properties. The molecule may be in several charged states from +2 to -2. It has been observed that the HOMO-LUMO gap is strongly reduced in solid state environment with metallic electrodes, as compared to the vacuum. This reduction is attributed to the image charges generated in the source and drain electrodes. This results in strong localization of charges in the molecule, a phenomenon addressed earlier. The charging energy has been calculated in vacuum and in SET environment. The interaction between molecule and the electrodes is treated self-consistently through Poisson equation. The charge stability diagram of the smallest molecular SET has been obtained. BibTeX: @article{Husain2015, title = {First-Principles Modeling of the Smallest Molecular Single Electron Transistor}, author = {Husain, Mudassir M and Kumar, Maneesh}, journal = {Journal of Atomic, Molecular, Condensate and Nano Physics}, volume = {2}, number = {1}, pages = {33--39}, year = {2015}, keywords = {Charge stability diagram,Coulomb blockade,Ethyne,Incoherent transport,Quantum tunneling,Single electron transistor,area:molecular electronics}, area = {molecular electronics} url = {http://www.rgnpublications.com/journals/index.php/jamcnp/article/view/270}, }  Anders Blom, Umberto Martinez Pozzoni, Troels Markussen & Kurt Stokbro, First-principles simulations of nanoscale transistors, Vol. 2015-Octob pp. 52--55 (2015) FinFET,QWpaper,area:semi,atomistic,density-functional theory,first-principles,simulation,transistor,ultrascaled device semi Abstract: We describe the transport characteristics of a 50 nm (gate length) 2D InAs tunnel field-effect n-i-n transistor in a double-gate fin-like geometry (fin width 2.3 nm) by means of atomic-scale simulations. In particular, we compare results from density functional theory (DFT) using the Meta-GGA exchange correlation potential with those from a tight-binding Hamiltonian. For the first time we show that the two methods give comparable results, proving the predictive power of atomic-scale simulations for this type of devices, and that it is possible to accurately study realistic ultrascaled devices with first-principles methods. BibTeX: @inproceedings{Blom2015, title = {First-principles simulations of nanoscale transistors}, author = {Blom, Anders and Pozzoni, Umberto Martinez and Markussen, Troels and Stokbro, Kurt}, booktitle = {International Conference on Simulation of Semiconductor Processes and Devices, SISPAD}, volume = {2015-Octob}, pages = {52--55}, year = {2015}, keywords = {FinFET,QWpaper,area:semi,atomistic,density-functional theory,first-principles,simulation,transistor,ultrascaled device}, area = {semi} doi = {10.1109/SISPAD.2015.7292256}, }  Sudhanshu Choudhary & Mayur Varshney, First-Principles Study of Spin Transport in CrO2-CNT-CrO2 Magnetic Tunnel Junction, Journal of Superconductivity and Novel Magnetism, Vol. 28(10), pp. 3141--3145 (2015) Carbon nanotube (CNT),DOPED SIC NANOTUBE,Half-metallic ferromagnet (HMF) electrodes,Magnetic tunnel junction (MTJ),Spin efficiency,Tunnel magnetoresistance (TMR),area:spintronics spintronics Abstract: We report first-principles calculations of spin-dependent quantum transport in magnetic tunnel junction (MTJ) consisting of carbon nanotube (CNT) sandwiched between two CrO2 half-metallic ferromagnet (HMF) electrodes. A large value of tunnel magnetoresistance (TMR) and perfect spin filtration is obtained using HMF electrodes in comparison to MTJs with ferromagnetic (FM) electrodes reported in past. The results suggest that HMF electrodes are more suitable over FM electrodes for implementing CNT-based MTJs. For this structure, the total spin current in parallel configuration is much larger than the total spin current in antiparallel configuration in the bias voltage range 0 to 1 V. Therefore, a high value of TMR  100 % is obtained at zero bias voltage which remains almost constant in the range of 0 to 1 V. The higher value of TMR and perfect spin filtration obtained with HMF electrodes recommends the importance of this structure in spin valves and other spin-based devices. The spin-dependent non-equilibrium transport is also investigated by analyzing the bias-dependent transmission coefficients. BibTeX: @article{Choudhary2015, title = {First-Principles Study of Spin Transport in CrO2-CNT-CrO2 Magnetic Tunnel Junction}, author = {Choudhary, Sudhanshu and Varshney, Mayur}, journal = {Journal of Superconductivity and Novel Magnetism}, volume = {28}, number = {10}, pages = {3141--3145}, year = {2015}, keywords = {Carbon nanotube (CNT),DOPED SIC NANOTUBE,Half-metallic ferromagnet (HMF) electrodes,Magnetic tunnel junction (MTJ),Spin efficiency,Tunnel magnetoresistance (TMR),area:spintronics}, area = {spintronics} doi = {10.1007/s10948-015-3142-2}, }  Sudhanshu Choudhary & Surendra Jalu, First-principles study of spin transport in Fe-SiCNT-Fe magnetic tunnel junction, Physics Letters A, Vol. 379(28-29), pp. 1661--1665 (2015) Sp,Spin injection,Tunnel magnetoresistance (TMR),area:nanotubes nanotubes Abstract: We report first-principles calculations of spin-dependent quantum transport in Fe-SiCNT-Fe magnetic tunnel junction (MTJ). Perfect spin filtration effect and substantial tunnel magnetoresistance are obtained, which suggests SiCNTs as a suitable candidate over CNTs for implementing 1D MTJs. The calculated tunnel magnetoresistance is several hundred percent at zero bias voltage, it reduces to nearly zero after the bias voltage of about 1 V. When the orientation of magnetic configurations of both electrodes is parallel, the zero bias spin injection factor is staggering 99% and remains reasonably high in the range of 60%-75% after the bias voltage of 0.6 V. BibTeX: @article{Choudhary2015b, title = {First-principles study of spin transport in Fe-SiCNT-Fe magnetic tunnel junction}, author = {Choudhary, Sudhanshu and Jalu, Surendra}, journal = {Physics Letters A}, volume = {379}, number = {28-29}, pages = {1661--1665}, year = {2015}, keywords = {Sp,Spin injection,Tunnel magnetoresistance (TMR),area:nanotubes}, area = {nanotubes} doi = {10.1016/j.physleta.2015.04.041}, }  Wen Liu, Jie Cheng, Jian-Hua Zhao, Cai-Juan Xia & De-Sheng Liu, Gate-modulated electronic transport through a graphene nanoribbon composed of nanoribbons of different widths, Journal of Theoretical and Computational Chemistry, Vol. 14(01), pp. 1550005 (2015) Graphene nanoribbon,RESISTANCE,area:graphene,electronic transport,negative differential resistance graphene Abstract: Based on the non-equilibrium Green's function (NEGF) method combined with the density functional theory (DFT), we have studied the gate-modulated electronic properties of a graphene nanoribbon (GNR) which is composed of two GNRs of different widths. The results show that the charge transport is greatly modulated by the applied gate. Negative differential resistance (NDR) behaviors is found in such a system. With the increase in the gate, the NDR behaviors will disappear and reappear. Furthermore, under certain gate voltages multiple NDR behavior is found, the origin of which is attributed to the change of the number of effective transport channels and the variation of delocalization degree of the orbitals within the bias window. Interestingly, low bias NDR behavior is obtained which is desirable for integrated circuits from the point view of power consumption. BibTeX: @article{Liu2015a, title = {Gate-modulated electronic transport through a graphene nanoribbon composed of nanoribbons of different widths}, author = {Liu, Wen and Cheng, Jie and Zhao, Jian-Hua and Xia, Cai-Juan and Liu, De-Sheng}, journal = {Journal of Theoretical and Computational Chemistry}, volume = {14}, number = {01}, pages = {1550005}, year = {2015}, keywords = {Graphene nanoribbon,RESISTANCE,area:graphene,electronic transport,negative differential resistance}, area = {graphene} doi = {10.1142/S0219633615500054}, }  Can Cao, Meng-qiu Long, Xiao-jiao Zhang & Xian-cheng Mao, Giant magnetoresistance and spin-filtering effects in zigzag graphene and hexagonal boron nitride based heterojunction, Physics Letters A, Vol. 379(24-25), pp. 1527--1531 (2015) Electronic transport property,Giant magnetoresistance,Heterojunction,Rectifying effect,Spin-filtering effect,area:2dmat,area:materials 2dmat,materials Abstract: The spin-dependent electronic transport properties of heterojunction constructed by bare zigzag graphene nanoribbon and hexagonal boron nitride nanoribbon are investigated by the non-equilibrium Green's function method in combination with the density functional theory. The results show that the giant magnetoresistance effect can be realized in the heterojunction, and the magnetoresistance ratio can reach to 106. Moreover, it is found that the heterojunction is a good spin-filtering device with nearly 100% spin filtering efficiency at a wide bias voltage region in both ferromagnetic and antiferromagnetic magnetic configurations. BibTeX: @article{Cao2015, title = {Giant magnetoresistance and spin-filtering effects in zigzag graphene and hexagonal boron nitride based heterojunction}, author = {Cao, Can and Long, Meng-qiu and Zhang, Xiao-jiao and Mao, Xian-cheng}, journal = {Physics Letters A}, volume = {379}, number = {24-25}, pages = {1527--1531}, year = {2015}, keywords = {Electronic transport property,Giant magnetoresistance,Heterojunction,Rectifying effect,Spin-filtering effect,area:2dmat,area:materials}, area = {2dmat,materials} doi = {10.1016/j.physleta.2015.03.036}, }  Li Peng, Kailun Yao, Ruqian Wu, Shuling Wang, Sicong Zhu, Yun Ni, Fengxia Zu, Zuli Liu & Bin Guo, Giant magnetoresistance in zigzag MoS 2 nanoribbons, Phys. Chem. Chem. Phys., Vol. 17(15), pp. 10074--10079 (2015) area:2dmat 2dmat Abstract: Using first principles calculations based on density functional theory, we investigated the transport properties of zigzag MoS2 nanoribbons with parallel and antiparallel spin configurations. The results show that the parallel configuration has conventional metallic properties while the antiparallel configuration presents semiconductor properties. Consequently, the conduction calculations predict that the zigzag MoS2 nanoribbons exhibit the giant magnetoresistance effect with a value over four orders of magnitude at room temperature by altering the configuration from the parallel to the antiparallel spin junction. By analyzing the spin-resolved band structures of zigzag MoS2 nanoribbons, we clarify that the orbital mismatching near the Fermi level between spin up and spin down is a key factor to generate this large magnetoresistance. Our results indicate that the giant magnetoresistance effect in the zigzag MoS2 nanoribbons remains robust to the change in the ribbon widths and lengths. BibTeX: @article{Peng2015, title = {Giant magnetoresistance in zigzag MoS 2 nanoribbons}, author = {Peng, Li and Yao, Kailun and Wu, Ruqian and Wang, Shuling and Zhu, Sicong and Ni, Yun and Zu, Fengxia and Liu, Zuli and Guo, Bin}, journal = {Phys. Chem. Chem. Phys.}, publisher = {The Royal Society of Chemistry}, volume = {17}, number = {15}, pages = {10074--10079}, year = {2015}, keywords = {area:2dmat}, area = {2dmat} doi = {10.1039/C4CP04892J}, }  X.F. Yang, H.L. Wang, Y.S. Chen, Y.W. Kuang, X.K. Hong, Y.S. Liu, J.F. Feng & X.F. Wang, Giant spin thermoelectric effects in all-carbon nanojunctions, Physical chemistry chemical physics : PCCP, Vol. 17(35), pp. 22815--22 (2015) area:graphene,area:molecular electronics graphene,molecular electronics Abstract: We examine the thermospin properties of an all-carbon nanojunction constructed by a graphene nanoflake (GNF) and zigzag-edged graphene nanoribbons (ZGNRs), bridged by the carbon atomic chains. The first-principles calculations show that the phonon thermal conductance is much weaker than the electron thermal conductance at the Fermi level, and even the former is a few percent of the latter in the low-temperature regime. In the meantime, the carbon-based device possesses an excellent spin transport property at the Fermi level due to the appearance of half-metallic property. Furthermore, the single-spin Seebeck coefficient has a larger value at the Fermi level. These facts ultimately result in a significant enhancement of spin thermoelectric figure of merit (FOM) ZST. By controlling the carbon-chain lengths and the temperature, the maximal value of ZST can reach 30. Moreover, we also find that the room temperature ZST displays an odd-even effect with the carbon-chain lengths, and it is always larger than the charge thermoelectric FOM ZCT. BibTeX: @article{Yang2015b, title = {Giant spin thermoelectric effects in all-carbon nanojunctions}, author = {Yang, X F and Wang, H L and Chen, Y S and Kuang, Y W and Hong, X K and Liu, Y S and Feng, J F and Wang, X F}, journal = {Physical chemistry chemical physics : PCCP}, publisher = {Royal Society of Chemistry}, volume = {17}, number = {35}, pages = {22815--22}, year = {2015}, keywords = {area:graphene,area:molecular electronics}, area = {graphene,molecular electronics} doi = {10.1039/c5cp02779a}, }  Yuanyuan Pan, Yangyang Wang, Lu Wang, Hongxia Zhong, Ruge Quhe, Zeyuan Ni, Meng Ye, Wai-Ning Mei, Junjie Shi, Wanlin Guo, Jinbo Yang & Jing Lu, Graphdiyne-metal contacts and graphdiyne transistors, Nanoscale, Vol. 7 pp. 2116--2127 (2015) area:graphene,graphdyine graphene Abstract: Graphdiyne was prepared on a metal surface, and the preparation of devices using it inevitably involves its contact with metals. Using density functional theory with dispersion correction, we systematically studied, for the first time, the interfacial properties of graphdiyne that is in contact with a series of metals (Al, Ag, Cu, Au, Ir, Pt, Ni, and Pd). Graphdiyne forms an n-type Ohmic or quasi-Ohmic contact with Al, Ag, and Cu, while it forms a Schottky contact with Pd, Au, Pt, Ni, and Ir (at the source/drain-channel interface), with high Schottky barrier heights of 0.21, 0.46 (n-type), 0.30, 0.41, and 0.46 (p-type) eV, respectively. A graphdiyne field effect transistor (FET) with Al electrodes was simulated using quantum transport calculations. This device exhibits an on-off ratio up to 104 and a very large on-state current of 1.3 [times] 104 mA mm-1 in a 10 nm channel length. Thus, a new prospect has opened up for graphdiyne in high performance nanoscale devices. BibTeX: @article{Pan2015, title = {Graphdiyne-metal contacts and graphdiyne transistors}, author = {Pan, Yuanyuan and Wang, Yangyang and Wang, Lu and Zhong, Hongxia and Quhe, Ruge and Ni, Zeyuan and Ye, Meng and Mei, Wai-Ning and Shi, Junjie and Guo, Wanlin and Yang, Jinbo and Lu, Jing}, journal = {Nanoscale}, volume = {7}, pages = {2116--2127}, year = {2015}, keywords = {area:graphene,graphdyine}, area = {graphene} doi = {10.1039/c4nr06541g}, }  Wanzhi Qiu, Phuong Duc Nguyen & Efstratios Skafidas, Graphene nanopores as negative differential resistance devices, Journal of Applied Physics, Vol. 117(5), pp. 54306 (2015) DIODES,ELECTRONIC TRANSPORT,Electrodes,Graphene,MEMORY,NANORIBBONS,NDR,Negative resistance,PERFORMANCE,Passivation,TRANSISTORS,Transport properties,area:graphene graphene Abstract: We present graphene nanopores as new negative differential resistance (NDR) devices, and study their quantum transport properties using non-equilibrium Green's function and the density functional tight binding method. The proposed device structure is created on intrinsic armchair-edged graphene nanoribbons with uniform widths, where the central scattering region has a nanopore in the interior, and the two ends of the nanoribbon act naturally as connecting electrodes. We show that nitrogen-passivated scattering regions generally result in pronounced NDR properties, while hydrogen-passivated ones do not. This NDR effect occurs at low bias voltages, below 1?V, and achieves extraordinarily high peak-to-valley current ratio, while still attaining very high peak current densities. In addition, very sharp current peaks in the μA range can occur in the I-V curves, and through varying structural dimensions of the proposed structure multiple NDR regions can be realized. These results suggest that the device has promising potential in applications such as high frequency oscillators, memory devices, and fast switches. BibTeX: @article{Qiu2015, title = {Graphene nanopores as negative differential resistance devices}, author = {Qiu, Wanzhi and Nguyen, Phuong Duc and Skafidas, Efstratios}, journal = {Journal of Applied Physics}, volume = {117}, number = {5}, pages = {54306}, year = {2015}, keywords = {DIODES,ELECTRONIC TRANSPORT,Electrodes,Graphene,MEMORY,NANORIBBONS,NDR,Negative resistance,PERFORMANCE,Passivation,TRANSISTORS,Transport properties,area:graphene}, area = {graphene} doi = {10.1063/1.4907265}, }  Xi-Feng Yang, Wen-Qian Zhou, Xue-Kun Hong, Yu-Shen Liu, Xue-Feng Wang & Jin-Fu Feng, Half-metallic properties, single-spin negative differential resistance, and large single-spin Seebeck effects induced by chemical doping in zigzag-edged graphene nanoribbons, The Journal of Chemical Physics, Vol. 142(2), pp. 24706 (2015) Doping,Electric currents,Fermi levels,Localized states,Thermoelectric effects,area:graphene,area:spintronics,area:thermo graphene,spintronics,thermo Abstract: Ab initio calculations combining density-functional theory and nonequilibrium Green's function are performed to investigate the effects of either single B atom or single N atom dopant in zigzag-edged graphene nanoribbons (ZGNRs) with the ferromagnetic state on the spin-dependent transport properties and thermospin performances. A spin-up (spin-down) localized state near the Fermi level can be induced by these dopants, resulting in a half-metallic property with 100% negative (positive) spin polarization at the Fermi level due to the destructive quantum interference effects. In addition, the highly spin-polarized electric current in the low bias-voltage regime and single-spin negative differential resistance in the high bias-voltage regime are also observed in these doped ZGNRs. Moreover, the large spin-up (spin-down) Seebeck coefficient and the very weak spin-down (spin-up) Seebeck effect of the B(N)-doped ZGNRs near the Fermi level are simultaneously achieved, indicating that the spin Seebeck effect is comparable to the corresponding charge Seebeck effect. BibTeX: @article{Yang2015a, title = {Half-metallic properties, single-spin negative differential resistance, and large single-spin Seebeck effects induced by chemical doping in zigzag-edged graphene nanoribbons}, author = {Yang, Xi-Feng and Zhou, Wen-Qian and Hong, Xue-Kun and Liu, Yu-Shen and Wang, Xue-Feng and Feng, Jin-Fu}, journal = {The Journal of Chemical Physics}, volume = {142}, number = {2}, pages = {24706}, year = {2015}, keywords = {Doping,Electric currents,Fermi levels,Localized states,Thermoelectric effects,area:graphene,area:spintronics,area:thermo}, area = {graphene,spintronics,thermo} doi = {10.1063/1.4904295}, }  Hari Mohan Rai, Shailendra K. Saxena, Vikash Mishra, Ravikiran Late, Rajesh Kumar, Pankaj R. Sagdeo, Neeraj K. Jaiswal & Pankaj Srivastava, Half-metallicity in armchair boron nitride nanoribbons: A first-principles study, Solid State Communications, Vol. 212 pp. 19--24 (2015) A. Boron nitride,A. nanoribbons,D. Density of st,area:materials materials Abstract: Using density functional theory, we predict half-metallicity in edge hydrogenated armchair boron nitride nanoribbons (ABNNRs). The predicted spin polarization is analyzed in detail by calculating electronic and magnetic properties of these hydrogenated ABNNRs by means of first-principles calculations within the local spin-density approximation (LSDA). ABNNRs with only edge B atoms passivated by H atoms are found to be half-metallic (regardless of their width) with a half-metal gap of 0.26 eV. Upto 100% spin polarized charge transport is predicted across the Fermi level owing to the giant spin splitting. Transmission spectrum analysis also confirms the separation of spin up and spindown electronic channels. It is revealed that H-passivation of only edge N atoms transforms non-magnetic bare ribbons into energetically stable magnetic semiconductors whereas hydrogenation of both the edges does not affect the electronic and magnetic state of bare ribbons significantly. The results are promising towards the realization of inorganic spintronic devices. BibTeX: @article{Rai2015, title = {Half-metallicity in armchair boron nitride nanoribbons: A first-principles study}, author = {Rai, Hari Mohan and Saxena, Shailendra K and Mishra, Vikash and Late, Ravikiran and Kumar, Rajesh and Sagdeo, Pankaj R and Jaiswal, Neeraj K and Srivastava, Pankaj}, journal = {Solid State Communications}, volume = {212}, pages = {19--24}, year = {2015}, keywords = {A. Boron nitride,A. nanoribbons,D. Density of st,area:materials}, area = {materials} doi = {10.1016/j.ssc.2015.04.003}, }  Md Sharafat Hossain, Feras Al-Dirini, Faruque M. Hossain & Efstratios Skafidas, High Performance Graphene Nano-ribbon Thermoelectric Devices by Incorporation and Dimensional Tuning of Nanopores, Scientific Reports, Vol. 5 pp. 11297 (2015) area:graphene graphene Abstract: Thermoelectric properties of Graphene nano-ribbons (GNRs) with nanopores (NPs) are explored for a range of pore dimensions in order to achieve a high performance two-dimensional nano-scale thermoelectric device. We reduce thermal conductivity of GNRs by introducing pores in them in order to enhance their thermoelectric performance. The electrical properties (Seebeck coefficient and conductivity) of the device usually degrade with pore inclusion; however, we tune the pore to its optimal dimension in order to minimize this degradation, enhancing the overall thermoelectric performance (high ZT value) of our device. We observe that the side channel width plays an important role to achieve optimal performance while the effect of pore length is less pronounced. This result is consistent with the fact that electronic conduction in GNRs is dominated along its edges. Ballistic transport regime is assumed and a semi-empirical method using Huckel basis set is used to obtain the electrical properties, while the phononic system is characterized by Tersoff empirical potential model. The proposed device structure has potential applications as a nanoscale local cooler and as a thermoelectric power generator. BibTeX: @article{Hossain2015, title = {High Performance Graphene Nano-ribbon Thermoelectric Devices by Incorporation and Dimensional Tuning of Nanopores}, author = {Sharafat Hossain, Md and Al-Dirini, Feras and Hossain, Faruque M and Skafidas, Efstratios}, journal = {Scientific Reports}, publisher = {Nature Publishing Group}, volume = {5}, pages = {11297}, year = {2015}, keywords = {area:graphene}, area = {graphene} doi = {10.1038/srep11297}, }  Feras Al-Dirini, Faruque M. Hossain, Mahmood A. Mohammed, Ampalavanapillai Nirmalathas & Efstratios Skafidas, Highly Effective Conductance Modulation in Planar Silicene Field Effect Devices Due to Buckling, Scientific Reports, Vol. 5 pp. 14815 (2015) Electrical and electronic engineering,Electronic and spintronic devices,Electronic devices,area:2dmat,silicene,transmission pathways 2dmat Abstract: Silicene is an exciting two-dimensional material that shares many of graphene's electronic properties, but differs in its structural buckling. This buckling allows opening a bandgap in silicene through the application of a perpendicular electric field. Here we show that this buckling also enables highly effective modulation of silicene's conductance by means of an in-plane electric field applied through silicene side gates, which can be realized concurrently within the same silicene monolayer. We illustrate this by using silicene to implement Self-Switching Diodes (SSDs), which are two-dimensional field effect nanorectifiers realized within a single silicene monolayer. Our quantum simulation results show that the atomically-thin silicene SSDs, with sub-10 nm dimensions, achieve a current rectification ratio that exceeds 200, without the need for doping, representing a 30 fold enhancement over graphene SSDs. We attribute this enhancement to a bandgap opening due to the in-plane electric field, as a consequence of silicene's buckling. Our results suggest that silicene is a promising material for the realization of planar field effect devices. BibTeX: @article{Al-Dirini2015, title = {Highly Effective Conductance Modulation in Planar Silicene Field Effect Devices Due to Buckling}, author = {Al-Dirini, Feras and Hossain, Faruque M and Mohammed, Mahmood A and Nirmalathas, Ampalavanapillai and Skafidas, Efstratios}, journal = {Scientific Reports}, publisher = {Nature Publishing Group}, volume = {5}, pages = {14815}, year = {2015}, keywords = {Electrical and electronic engineering,Electronic and spintronic devices,Electronic devices,area:2dmat,silicene,transmission pathways}, area = {2dmat} doi = {10.1038/srep14815}, }  X.Q. Deng, Z.H. Zhang & C.H. Yang, Improving the bias range for spin-filtering by selecting proper electrode materials, RSC Advances, Vol. 5(21), pp. 15812--15817 (2015) area:graphene,area:spintronics,nanoribbon graphene,spintronics Abstract: Using the non-equilibrium Green's function method combined with density function theory, we investigate the spin transport for carbon chains connected to electrodes of different materials. When a carbon chain is linked to the C-H (C-H2) bonded edges of H2-ZGNR-H, the carbon chain displays a net spin polarization with a net magnetic moment of 1.367 μB (-0.935 μB) for the C-H (C-H2) bonded edge contacts, but the directions of the net magnetic moment are opposite, and the latter system shows a larger spin conductance. Then, we choose N-doped H2-ZGNR-H as the left electrode, and the right electrode is replaced with a single-capped carbon nanotube, armchair graphene nanoribbon (AGNR), or gold electrode. The conductance and the bias range for perfect spin-filtering of these systems shows obvious differences: the carbon nanotube (Au) system shows weaker conductance, and the AGNR system shows the largest bias range for perfect spin-filtering. BibTeX: @article{Deng2015, title = {Improving the bias range for spin-filtering by selecting proper electrode materials}, author = {Deng, X Q and Zhang, Z H and Yang, C H}, journal = {RSC Advances}, publisher = {The Royal Society of Chemistry}, volume = {5}, number = {21}, pages = {15812--15817}, year = {2015}, keywords = {area:graphene,area:spintronics,nanoribbon}, area = {graphene,spintronics} doi = {10.1039/C4RA15272G}, }  Jun Peng, Yan Hong Zhou & Ke Qiu Chen, Influence of boundary types on rectifying behaviors in hexagonal boron-nitride/graphene nanoribbon heterojunctions, Organic Electronics: physics, materials, applications, Vol. 27 pp. 137--142 (2015) Boron-nitride/graphene nanoribbon heterojunctions,Boundary types,Rectifying behavior,area:2dmat,area:graphene 2dmat,graphene Abstract: We investigate the effect of boundary types on the rectifying behaviors in heterojunction composed of zigzag graphene and hexagonal boron-nitride (BNC) hybridized nanoribbons by employing nonequilibrium Green's functions in combination with the density-functional theory. The results demonstrate that the rectifying behavior is strongly dependent on the boundary types, while little affected by the width of BNC hybridized nanoribbons. It is noteworthy that the maximum rectifying ratio of the system at finite bias can be high up to orders of 107 in which atoms carbon in graphene nanoribbon are totally connected with atoms nitrogen in boron-nitride nanoribbon. The mechanism is proposed for these phenomena. BibTeX: @article{Peng2015a, title = {Influence of boundary types on rectifying behaviors in hexagonal boron-nitride/graphene nanoribbon heterojunctions}, author = {Peng, Jun and Zhou, Yan Hong and Chen, Ke Qiu}, journal = {Organic Electronics: physics, materials, applications}, publisher = {Elsevier B.V}, volume = {27}, pages = {137--142}, year = {2015}, keywords = {Boron-nitride/graphene nanoribbon heterojunctions,Boundary types,Rectifying behavior,area:2dmat,area:graphene}, area = {2dmat,graphene} doi = {10.1016/j.orgel.2015.09.005}, }  F. Fuchs, A. Zienert, C. Wagner, J. Schuster & S.E. Schulz, Interaction between carbon nanotubes and metals: Electronic properties, stability, and sensing, Microelectronic Engineering, Vol. 137 pp. 124--129 (2015) Acceleration sensor,Adatom stability,BAND-GAPS,Carbon nanotube,Density functional theory,Metal contact,Metal decoration,NANOPARTICLES,SI,TRANSPORT-PROPERTIES,area:materials,area:nanotubes materials,nanotubes Abstract: The interactions between carbon nanotubes (CNTs) and metal adatoms as well as metal contacts are studied by means of ab initio electronic structure calculations. We show that the electronic properties of a semiconducting (8,4) CNT can be modified by small amounts of Pd adatoms. Such a decoration conserves the piezoelectric properties of the CNT. Besides the electronic influence, the stability of a single adatom, which is of big importance for future technology applications, is investigated as well. We find only small energy barriers for the diffusion of a Pd adatom on the CNT surface. Thus, single Pd adatoms will be mobile at room temperature. Finally we present results for the interaction between a metallic (6,0) CNT and metal surfaces. Binding energies and distances for Al, Cu, Pd, Ag, Pt, and Au are discussed and compared, showing remarkable agreement between the interaction of single metal atoms and metal surfaces with CNTs. BibTeX: @article{Fuchs2015, title = {Interaction between carbon nanotubes and metals: Electronic properties, stability, and sensing}, author = {Fuchs, F and Zienert, A and Wagner, C and Schuster, J and Schulz, S E}, journal = {Microelectronic Engineering}, volume = {137}, pages = {124--129}, year = {2015}, keywords = {Acceleration sensor,Adatom stability,BAND-GAPS,Carbon nanotube,Density functional theory,Metal contact,Metal decoration,NANOPARTICLES,SI,TRANSPORT-PROPERTIES,area:materials,area:nanotubes}, area = {materials,nanotubes} doi = {10.1016/j.mee.2015.02.003}, }  Jian Shao, X.Y. Zhang, Yue Zheng, Biao Wang & Yun Chen, Length-dependent rectification and negative differential resistance in heterometallic n-alkanedithiol junctions, RSC Advances, Vol. 5(18), pp. 13917--13922 (2015) area:molecular electronics molecular electronics Abstract: The transport properties of heterometallic n-alkanedithiol junctions have been investigated via first-principles calculations. Results show that the heterometallic n-alkanedithiol junctions exhibit significant rectification at lower voltage. A negative differential resistance was found at higher voltage, which increases with the increase of the n-alkanedithiol backbone length. In order to explain these phenomena, the molecular orbitals of n-alkanedithiol have been analyzed between certain electrodes. It is found that the rectification is induced by asymmetric orbital profiles between the heterometallic electrodes, and negative differential resistance arises when the molecular orbitals cross the band edge provided by the metal-sulfur bond. BibTeX: @article{Shao2015, title = {Length-dependent rectification and negative differential resistance in heterometallic n-alkanedithiol junctions}, author = {Shao, Jian and Zhang, X Y and Zheng, Yue and Wang, Biao and Chen, Yun}, journal = {RSC Advances}, publisher = {The Royal Society of Chemistry}, volume = {5}, number = {18}, pages = {13917--13922}, year = {2015}, keywords = {area:molecular electronics}, area = {molecular electronics} doi = {10.1039/C4RA14999H}, }  J. Li, Z.H. Zhang, X.Q. Deng, Z.Q. Fan & G.P. Tang, Magnetic transport properties of a trigonal graphene sandwiched between graphene nanoribbon electrodes, Carbon, Vol. 93 pp. 335--341 (2015) HETEROJUNCTIONS,JUNCTIONS,LAYER GRAPHENE,MAGNETORESISTANCE,RECTIFICATION,RECTIFYING BEHAVIORS,ROOM-TEMPERATURE,area:molecular electronics molecular electronics Abstract: Magnetic transport behaviors of a zigzag-edge trigonal graphene (ZTG) constructed as a nanodevice with zigzag graphene nanoribbon (ZGNR) electrodes are investigated, and various magnetic configurations are considered. It is found that excellent magnetic device natures, such as the perfect (100%) spin polarization in a large bias region, spin-resolved rectification ratios approaching ∼105, and the giant magnetoresistance effect up to ∼1015%, can be achieved, which is indeed an extremely high value as compared with previously reported theoretical one, ∼107%, for complete ZGNR-based magnetic devices and experimental ones, ∼104%, for the MgO tunnel junction. This can be attributed to unique transmission features due to the strong modulating ability of ZTG for the magnetic transport. These results suggest that the ZTG might possess some advantages in nature for developing magnetic devices. BibTeX: @article{Li2015, title = {Magnetic transport properties of a trigonal graphene sandwiched between graphene nanoribbon electrodes}, author = {Li, J and Zhang, Z H and Deng, X Q and Fan, Z Q and Tang, G P}, journal = {Carbon}, volume = {93}, pages = {335--341}, year = {2015}, keywords = {HETEROJUNCTIONS,JUNCTIONS,LAYER GRAPHENE,MAGNETORESISTANCE,RECTIFICATION,RECTIFYING BEHAVIORS,ROOM-TEMPERATURE,area:molecular electronics}, area = {molecular electronics} doi = {10.1016/j.carbon.2015.05.050}, }  Qiu Hua Wu, Peng Zhao & Gang Chen, Magnetic transport properties of DBTAA-based nanodevices with graphene nanoribbon electrodes, Organic Electronics: physics, materials, applications, Vol. 25 pp. 308--316 (2015) DEVICE,EDGE,GIANT MAGNETORESISTANCE,Giant magnetoresistance,MOLECULAR-SPINTRONICS,SPIN,Spin-filtering,Spin-polarized current rectifying,TRANSITION,area:molecular electronics molecular electronics Abstract: Based on the density functional theory combined with the nonequilibrium Green's function formalism, the magnetic transport properties of dibenzotetraaza[14]annulene (DBTAA) and transition metal (TM)-DBTAA (TM = Fe and Co) sandwiched between two ferromagnetic zigzag-edge graphene nanoribbon electrodes are investigated. The results show that giant magnetoresistance, spin-filtering and spin-polarized current rectifying effects can be realized simultaneously in the DBTAA system by modulating the external magnetic field. Introducing of TM atoms has obvious effects on these spin-related effects. The mechanisms of these intriguing phenomena are proposed and these phenomena would be instructive in the design of high-performance magnetic nanodevices. BibTeX: @article{Wu2015b, title = {Magnetic transport properties of DBTAA-based nanodevices with graphene nanoribbon electrodes}, author = {Wu, Qiu Hua and Zhao, Peng and Chen, Gang}, journal = {Organic Electronics: physics, materials, applications}, publisher = {Elsevier B.V.}, volume = {25}, pages = {308--316}, year = {2015}, keywords = {DEVICE,EDGE,GIANT MAGNETORESISTANCE,Giant magnetoresistance,MOLECULAR-SPINTRONICS,SPIN,Spin-filtering,Spin-polarized current rectifying,TRANSITION,area:molecular electronics}, area = {molecular electronics} doi = {10.1016/j.orgel.2015.07.013}, }  Z.L. Yu, D. Wang, Z. Zhu & Z.H. Zhang, Magneto-electronic properties of graphene nanoribbons with various edge structures passivated by phosphorus and hydrogen atoms, Physical Chemistry Chemical Physics, Vol. 17(37), pp. 24020--24028 (2015) area:graphene,half-metallicity,nanoribbons graphene Abstract: The electronic and magnetic structures of graphene nanoribbons (GNRs) with various edge structures passivated by P atoms are investigated systematically, and compared with H passivation as well. GNRs with the entire reconstructed Klein edge or armchair edge are found to be nonmagnetic regardless of P or H passivation. However, if the edge of GNRs is a mixture of zigzag edge and reconstructed Klein edge, they are nonmagnetic for H passivation but significantly magnetic for P passivation, which could be attributed to the "charge transfer doping'' effect. And the corresponding magnetic device shows a noticeable negative differential resistance phenomenon and an excellent spin filtering effect under AP configuration, which originate from the special energy band structure. The GNRs with zigzag edge, reconstructed Klein edge, or mixed edge shapes are all metals in the nonmagnetic state regardless of the H or P atoms involved. The relationship between the energy gap and the width in armchair-edged GNRs by P passivation with a dimer structure also satisfies the 3p periodicity, but different in detail from the case of H passivation. The calculated edge formation energy indicates that P-passivated GNRs are energetically more favorable, suggesting that they can stably exist in the experiment. BibTeX: @article{Yu2015b, title = {Magneto-electronic properties of graphene nanoribbons with various edge structures passivated by phosphorus and hydrogen atoms}, author = {Yu, Z L and Wang, D and Zhu, Z and Zhang, Z H}, journal = {Physical Chemistry Chemical Physics}, volume = {17}, number = {37}, pages = {24020--24028}, year = {2015}, keywords = {area:graphene,half-metallicity,nanoribbons}, area = {graphene} doi = {10.1039/c5cp03927d}, }  Fang Xie, Zhi-Qiang Fan, Kun Liu, Hai-Yan Wang, Ji-Hai Yu & Ke-Qiu Chen, Negative differential resistance and stable conductance switching behaviors of salicylideneaniline molecular devices sandwiched between armchair graphene nanoribbon electrodes, Organic Electronics, Vol. 27 pp. 41--45 (2015) Conductance switching,Density-functional theory,Molecular device,Negative differential resistance,Nonequilibrium Green's functions,area:molecular electronics molecular electronics Abstract: By applying nonequilibrium Green's functions in combination with the density-functional theory, we investigate the electron transport properties of the salicylideneaniline molecule sandwiched between two armchair graphene nanoribbon (AGNR) electrodes. It shows that the width of the AGNR electrodes plays a significant role in the transport properties of the salicylideneaniline molecular junctions. The current–voltage characteristics of the salicylideneaniline molecule sandwiched between 8AGNR electrodes can perform a stable conductance switching behavior at the bias region [1.2 V, 1.6 V] when the molecule translates between the trans-enol form and the trans-keto form. When the electrodes change to 7AGNR, a remarkable negative differential resistance behavior can be found in the salicylideneaniline molecular device at the trans-keto form. That means the salicylideneaniline molecule can perform different functions when it connects to the different AGNR electrodes. BibTeX: @article{Xie2015, title = {Negative differential resistance and stable conductance switching behaviors of salicylideneaniline molecular devices sandwiched between armchair graphene nanoribbon electrodes}, author = {Xie, Fang and Fan, Zhi-Qiang and Liu, Kun and Wang, Hai-Yan and Yu, Ji-Hai and Chen, Ke-Qiu}, journal = {Organic Electronics}, publisher = {Elsevier B.V}, volume = {27}, pages = {41--45}, year = {2015}, keywords = {Conductance switching,Density-functional theory,Molecular device,Negative differential resistance,Nonequilibrium Green's functions,area:molecular electronics}, area = {molecular electronics} doi = {10.1016/j.orgel.2015.08.028}, }  Mudassir M. Husain & Maneesh Kumar, Negative differential resistance, rectifying performance and switching behaviour in carbon-chain based molecular devices, Organic Electronics: physics, materials, applications, Vol. 27 pp. 92--100 (2015) I-V characteristics,Mono atomic carbon chains,Multi switching,NEGF-DFT,Rectification ratio,Transmission spectrum,area:graphene,area:molecular electronics graphene,molecular electronics Abstract: Using non equilibrium Green's function formalism coupled with density functional theory, we carry out electronic transport calculation in two types of molecular devices, one constructed by linear monoatomic carbon chain (textperiodcenteredtextperiodcenteredtextperiodcenteredC-C-C-C textperiodcenteredtextperiodcenteredtextperiodcentered) and the other by two carbon chains capped with a phenyl ring (textperiodcenteredtextperiodcenteredtextperiodcenteredC-C-Ph-C-Ctextperiodcenteredtextperiodcenteredtextperiodcentered), sandwiched between two z-shape electrodes, constructed by zigzag-armchair-zigzag (zz-ac-zz) graphene nanoribbons (GNRs). The potential difference between the z-shape contacts can be varied by employing an external d.c. voltage source. Thus, one may observe the variation of conductivity through the channels. The current-voltage (I-V) characteristics of the proposed resistors show N-type negative differential resistance (NDR), within a particular voltage region. The figure of merit or PVR (peak to valley) ratio (Itextlessinftextgreaterpeaktextless/inftextgreater/Itextlessinftextgreatervalleytextless/inftextgreater) gets significantly increased, on capping the chains with phenyl ring. A higher value of PVR in I-V characteristics enhances the possibility of applications utilizing NDR. The calculated I-V characteristic is asymmetric and the rectification ratio is found to be 7, in case of the linear carbon chain. The rectification ratio R(V) = I(V)/I(-V) is an important parameter which determines, its suitability as rectifying device. It has been demonstrated that on varying the conformation of the phenyl ring with respect to the plane of electrodes, the transport properties of the system can be modulated. Interestingly, I-V characteristics are asymmetric and show dual NDR peaks in perpendicular conformation of the phenyl ring, with respect to the electrodes in the (textperiodcenteredtextperiodcenteredtextperiodcenteredC-C-Ph-C-Ctextperiodcenteredtextperiodcenteredtextperiodcentered) system. The figure of merit is found to be respectively 8 and 51 for the first and second NDR regions. The later value is extremely high, making it an excellent candidate for potential applications. Moreover, the multi peak NDR device may be widely used in multiple-valued logics. Only a limited number of multiple NDR peak molecular-based nano systems have so far been reported, which are quite complex; by contrast the present system seems to be quite simple. The physical phenomenon of NDR was explained in the light of molecular projected self-consistent Hamiltonian (MPSH) and also the evolution of the frontier molecular orbitals (HOMO-LUMO) as well as transmission under various external bias voltages. BibTeX: @article{Husain2015a, title = {Negative differential resistance, rectifying performance and switching behaviour in carbon-chain based molecular devices}, author = {Husain, Mudassir M. and Kumar, Maneesh}, journal = {Organic Electronics: physics, materials, applications}, publisher = {Elsevier B.V}, volume = {27}, pages = {92--100}, year = {2015}, keywords = {I-V characteristics,Mono atomic carbon chains,Multi switching,NEGF-DFT,Rectification ratio,Transmission spectrum,area:graphene,area:molecular electronics}, area = {graphene,molecular electronics} doi = {10.1016/j.orgel.2015.09.014}, }  Po-Hao Chang, Troels Markussen, Søren Smidstrup, Kurt Stokbro & Branislav K. Nikolić, Nonequilibrium spin texture within a thin layer below the surface of current-carrying topological insulator Bi2Se3: A first-principles quantum transport st, Physical Review B, Vol. 92(20), pp. 201406 (2015) QWpaper,Topological insulators,area:spin,area:spintronics spin,spintronics Abstract: We predict that unpolarized charge current injected into a ballistic thin film of prototypical topological insulator (TI) Bi2Se3 will generate a noncollinear spin texture S(r) on its surface. Furthermore, the nonequilibrium spin texture will extend into an ≅2-nm-thick layer below the TI surfaces due to penetration of evanescent wave functions from the metallic surfaces into the bulk of TI. Averaging S(r) over a few angstroms along the longitudinal direction defined by the current flow reveals a large component pointing in the transverse direction. In addition, we find an order of magnitude smaller out-of-plane component when the direction of injected current with respect to Bi and Se atoms probes the largest hexagonal warping of the Dirac-cone dispersion on the TI surface. Our analysis is based on an extension of the nonequilibrium Green's functions combined with density functional theory (NEGF+DFT) to situations involving noncollinear spins and spin-orbit coupling. We also demonstrate how DFT calculations with a properly optimized local orbital basis set can precisely match putatively more accurate calculations with a plane-wave basis set for the supercell of Bi2Se3. BibTeX: @article{Chang2015, title = {Nonequilibrium spin texture within a thin layer below the surface of current-carrying topological insulator Bi2Se3: A first-principles quantum transport st}, author = {Chang, Po-Hao and Markussen, Troels and Smidstrup, Søren and Stokbro, Kurt and Nikolić, Branislav K.}, journal = {Physical Review B}, publisher = {American Physical Society}, volume = {92}, number = {20}, pages = {201406}, year = {2015}, keywords = {QWpaper,Topological insulators,area:spin,area:spintronics}, area = {spin,spintronics} doi = {10.1103/PhysRevB.92.201406}, }  Sheng Yu, Kwesi Eshun, Hao Zhu & Qiliang Li, Novel Two-Dimensional Mechano-Electric Generators and Sensors Based on Transition Metal Dichalcogenides, Scientific reports, Vol. 5(April), pp. 12854 (2015) Electrical and electronic engineering,Nanosensors,area:2dmat,area:tmd 2dmat,tmd Abstract: Transition metal dichalcogenides (TMDCs), such as MoS2 and WSe2, provide two-dimensional atomic crystals with semiconductor band gap. In this work, we present a design of new mechano-electric generators and sensors based on transition metal dichalcogenide nanoribbon PN junctions and heterojunctions. The mechano-electric conversion was simulated by using a first-principle calculation. The output voltage of MoS2 nanoribbon PN junction increases with strain, reaching 0.036 V at 1% strain and 0.31 V at 8% strain, much larger than the reported results. Our study indicates that the length, width and layer number of TMDC nanoribbon PN junctions have an interesting but different impact on the voltage output. Also, the results indicate that doping position and concentration only cause a small fluctuation in the output voltage. These results have been compared with the mechano-electric conversion of TMDC heterojunctions. Such novel mechano-electric generators and sensors are very attractive for applications in future self-powered, wearable electronics and systems. BibTeX: @article{Yu2015a, title = {Novel Two-Dimensional Mechano-Electric Generators and Sensors Based on Transition Metal Dichalcogenides}, author = {Yu, Sheng and Eshun, Kwesi and Zhu, Hao and Li, Qiliang}, journal = {Scientific reports}, publisher = {Nature Publishing Group}, volume = {5}, number = {April}, pages = {12854}, year = {2015}, keywords = {Electrical and electronic engineering,Nanosensors,area:2dmat,area:tmd}, area = {2dmat,tmd} doi = {10.1038/srep12854}, }  Nikolai Lebedev, Syed Mahmud, Igor Griva, Anders Blom & Leonard M. Tender, On the electron transfer through Geobacter sulfurreducensPilA protein, Journal of Polymer Science Part B: Polymer Physics, Vol. 53(24), pp. 1706--1717 (2015) Geobacter sulfurreducens,area:molecular electronics,conductive pili,electroactive biofilm,molecular electronics,protein conductance molecular electronics Abstract: Geobacter sulfurreducens pili composed of the Type IV pili structural peptide PilA have been implicated as efficient electronic conductors. Though investigated experimentally, no detailed theoretical studies have been performed to date that provide quantitative estimation of the transmission spectrum, electron transfer (ET) paths, efficiency of current generation, and other factors needed for understanding possible mechanisms of conductivity. In the present work, we calculate from first principles the possibilities of electron tunneling through 3 PilA fragments which structure was identified recently by NMR. The results indicate that positively charged amino acids, arginines and lysines form electrostatic traps in the middle of the peptide preventing ET at low bias voltages (textless 6V). At higher biases the traps are filled with electrons making possible sequential electron tunneling through the central part of the protein. In addition, leucines and phenylalanines form ET loops facilitating electron stabilization within the protein and sequential ET. Our results indicate that ET through the PilA protein cannot occur by coherent ET, but suggest a sequential (incoherent) mechanism. textcopyright 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015, 53, 1706-1717 BibTeX: @article{Lebedev2015, title = {On the electron transfer through Geobacter sulfurreducensPilA protein}, author = {Lebedev, Nikolai and Mahmud, Syed and Griva, Igor and Blom, Anders and Tender, Leonard M}, journal = {Journal of Polymer Science Part B: Polymer Physics}, volume = {53}, number = {24}, pages = {1706--1717}, year = {2015}, keywords = {Geobacter sulfurreducens,area:molecular electronics,conductive pili,electroactive biofilm,molecular electronics,protein conductance}, area = {molecular electronics} doi = {10.1002/polb.23809}, }  Ganesh Hegde & R. Chris Bowen, On the feasibility of ab initio electronic structure calculations for Cu using a single s orbital basis, AIP Advances, Vol. 5(10), pp. 107142 (2015) Copper,Electrical resistivity,Electronic structure,Grain boundaries,Nanocrystalline materials,area:nanowires,area:semi,industrial nanowires,semi Abstract: The accuracy of a single s-orbital representation of Cu towards enabling multi-thousand atom ab initio calculations of electronic structure is evaluated in this work. If an electrostatic compensation charge of approximately 0.3 electrons per atom is used in this basis representation of copper, the electronic transmission in bulk and nanocrystalline Cu compares accurately to that obtained with a Double Zeta Polarized basis set. The use of this representation is analogous to the use of single band effective mass representation for semiconductor electronic structure. With a basis of just one s-orbital per Cu atom, the representation is extremely computationally efficient and can be used to provide much needed ab initio insight into electronic transport in nanocrystalline Cu interconnects at realistic dimensions. BibTeX: @article{Hegde2015, title = {On the feasibility of ab initio electronic structure calculations for Cu using a single s orbital basis}, author = {Hegde, Ganesh and Bowen, R. Chris}, journal = {AIP Advances}, volume = {5}, number = {10}, pages = {107142}, year = {2015}, keywords = {Copper,Electrical resistivity,Electronic structure,Grain boundaries,Nanocrystalline materials,area:nanowires,area:semi,industrial}, area = {nanowires,semi} doi = {10.1063/1.4935092}, }  Ravi K. Biroju, Gone Rajender & P.K. Giri, On the origin and tunability of blue and green photoluminescence from chemically derived graphene: Hydrogenation and oxygenation studies, Carbon, Vol. 95 pp. 228--238 (2015) area:graphene graphene Abstract: We report on the identification of structural defects and oxygenated functional groups responsible for blue and green photoluminescence (PL) from the chemically derived graphene (CDG) thin films with the help of Raman imaging/spectroscopy, high resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR) and PL analyses. In particular, we probe the role of in-plane and edge oxygenated functionalities on the evolution of visible PL emissions from CDGs after controlled hydrogenation and oxygenation studies. The assignments of the various PL bands were corroborated from thermogravimetric and FTIR analyses in the CDGs and are directly correlated with the Raman analysis. Our studies reveal that the PL emission spectrum in CDGs can be tuned by controlled hydrogen and oxygen treatments. Two green emission bands in the range of ???497-502 nm and ???534-551 nm are assigned to the COOH and C=O sub-band energy states belonging to the edge sites, while the blue emission is attributed to the localised states of sp2/sp3 domains and epoxy related in-plane functional groups in the CDG materials. Our study demonstrates the tunability of PL spectrum from CDG materials through selective manipulation of the functional groups at the in-plane defects and edge sites. BibTeX: @article{Biroju2015, title = {On the origin and tunability of blue and green photoluminescence from chemically derived graphene: Hydrogenation and oxygenation studies}, author = {Biroju, Ravi K. and Rajender, Gone and Giri, P. K.}, journal = {Carbon}, publisher = {Elsevier Ltd}, volume = {95}, pages = {228--238}, year = {2015}, keywords = {area:graphene}, area = {graphene} doi = {10.1016/j.carbon.2015.08.036}, }  Mikhail Erementchouk, M.A. Khan & Michael N. Leuenberger, Optical signatures of states bound to vacancy defects in monolayer MoS2, Phys. Rev. B, Vol. 92(12), pp. 121401 (2015) area:2dmat,area:tmd 2dmat,tmd Abstract: The nonzero thickness of single-layer (SL) MoS2 manifests in electron states forming classes of states that are even and odd with respect to reflections through the central plane. These states are energetically well separated: In particular, we show that pristine SL MoS2 exhibits two band gaps, Eg||=1.9 eV and Eg|=3.2 eV, for the optical in-plane and out-of-plane susceptibilities CHi and Chi, respectively. Because of this, odd states are often neglected, which effectively reduces SL MoS2 to a perfect two-dimensional system. We study states bound to defects in SL MoS2 with three types of vacancy defects (VDs), (i) Mo vacancy, (ii) S2 vacancy, and (iii) 3xMoS2 quantum antidot, and show that odd states play an equally important role as the even states. In particular, we show that odd states bound to VDs lead to resonances in χ| inside Eg| in SL MoS2 with VDs. Additionally, we demonstrate that the states bound to VDs are not necessarily confined to the band gap in the even subsystem, which necessitates extending the energy region affected by the bound states. BibTeX: @article{Erementchouk2015, title = {Optical signatures of states bound to vacancy defects in monolayer MoS2}, author = {Erementchouk, Mikhail and Khan, M A and Leuenberger, Michael N}, journal = {Phys. Rev. B}, publisher = {American Physical Society}, volume = {92}, number = {12}, pages = {121401}, year = {2015}, keywords = {area:2dmat,area:tmd}, area = {2dmat,tmd} doi = {10.1103/PhysRevB.92.121401}, }  Brahmanandam Javvaji, M. Ajmalghan, D. Roy Mahapatra, M.R.R. Rahman & G.M.M. Hegde, Optoelectronic properties of graphene on silicon substrate: effect of defects in graphene, Vol. 9357 pp. 93571X (2015) Dynamics,Engineering,Graphene,Nanostructures,Optoelectronics,Photodetectors,Photodiodes,Silicon,Simulations,Superlattices,Transistors,area:nanotubes,bandgap,defects,density of states,electronic band structure,optical conductivity,silicon nanotubes Abstract: Engineering of electronic energy band structure in graphene based nanostructures has several potential applications. Substrate induced bandgap opening in graphene results several optoelectronic properties due to the inter-band transitions. Various defects like structures, including Stone-Walls and higher-order defects are observed when a graphene sheet is exfoliated from graphite and in many other growth conditions. Existence of defect in graphene based nanostructures may cause changes in optoelectronic properties. Defect engineered graphene on silicon system are considered in this paper to study the tunability of optoelectronic properties. Graphene on silicon atomic system is equilibrated using molecular dynamics simulation scheme. Based on this study, we confirm the existence of a stable super-lattice. Density functional calculations are employed to determine the energy band structure for the super-lattice. Increase in the optical energy bandgap is observed with increasing of order of the complexity in the defect structure. Optical conductivity is computed as a function of incident electromagnetic energy which is also increasing with increase in the defect order. Tunability in optoelectronic properties will be useful in understanding graphene based design of photodetectors, photodiodes and tunnelling transistors. BibTeX: @inproceedings{Javvaji2015, title = {Optoelectronic properties of graphene on silicon substrate: effect of defects in graphene}, author = {Javvaji, Brahmanandam and Ajmalghan, M and Roy Mahapatra, D and Rahman, M.R. R and Hegde, G.M. M}, booktitle = {Proc. SPIE}, editor = {Witzigmann, Bernd and Osiski, Marek and Henneberger, Fritz and Arakawa, Yasuhiko}, volume = {9357}, pages = {93571X}, year = {2015}, keywords = {Dynamics,Engineering,Graphene,Nanostructures,Optoelectronics,Photodetectors,Photodiodes,Silicon,Simulations,Superlattices,Transistors,area:nanotubes,bandgap,defects,density of states,electronic band structure,optical conductivity,silicon}, area = {nanotubes} doi = {10.1117/12.2084796}, url = {10.1117/12.2084796}, }  Sheng Yu, Hao D. Xiong, Kwesi Eshun, Hui Yuan & Qiliang Li, Phase transition, effective mass and carrier mobility of MoS2 monolayer under tensile strain, Applied Surface Science, Vol. 325 pp. 27--32 (2015) MoS2 monolayer,Mobility enhancement,Phase transition,Strain effect,Two-dimensional materials,area:2dmat,area:tmd 2dmat,tmd Abstract: We report a computational study on the impact of tensile strain on MoS2 monolayer. The transition between direct and indirect bandgap structure and the transition between semiconductor and metal phases in the monolayer have been investigated with tensile strain along all direction configurations with both x-axis and y-axis components exy (ex and ey). Electron effective mass and the hole effective mass are isotropic for biaxial strain exy = ex = ey and anisotropic for exy with ex != ey. The carrier effective mass behaves differently along different directions in response to the tensile strain. In addition, the impact of strain on carrier mobility has been studied by using the deformation potential theory. The electron mobility increases over 10 times with the biaxial strain: ex = ey = 9.5%. Also, the mobility decreases monotonically with the increasing temperature as mu   1/T. These results are very important for future nanotechnology based on two-dimensional materials. BibTeX: @article{Yu2015, title = {Phase transition, effective mass and carrier mobility of MoS2 monolayer under tensile strain}, author = {Yu, Sheng and Xiong, Hao D and Eshun, Kwesi and Yuan, Hui and Li, Qiliang}, journal = {Applied Surface Science}, volume = {325}, pages = {27--32}, year = {2015}, keywords = {MoS2 monolayer,Mobility enhancement,Phase transition,Strain effect,Two-dimensional materials,area:2dmat,area:tmd}, area = {2dmat,tmd} doi = {10.1016/j.apsusc.2014.11.079}, }  Pankaj Srivastava, Subhra Dhar & Neeraj K. Jaiswal, Potential spin-polarized transport in gold-doped armchair graphene nanoribbons, Physics Letters A, Vol. 379(9), pp. 835--842 (2015) Adsorption,Armchair graphene nanoribbon,Current,Gold,Spin,Substitution,area:graphene graphene Abstract: Based on NEGF-DFT computations, systematic investigation of electronic, magnetic and transport properties of AGNRs are done by employing Au through different doping mechanisms. Remarkable Au-AGNR bonding is observed in case of substitution due to the presence of impurity at the edges. Both substitution and adsorption of Au on AGNR surface induce significant changes in the electronic spin transport of the sp2 hybridized carbon sheets. AGNRs are semiconducting with lower total energy for the FM configuration, and the I-V characteristics reveal semiconductor to metal transition of Au-doped AGNR. The spin injection is voltage controlled in all the investigated Au-doped AGNRs. BibTeX: @article{Srivastava2015d, title = {Potential spin-polarized transport in gold-doped armchair graphene nanoribbons}, author = {Srivastava, Pankaj and Dhar, Subhra and Jaiswal, Neeraj K}, journal = {Physics Letters A}, volume = {379}, number = {9}, pages = {835--842}, year = {2015}, keywords = {Adsorption,Armchair graphene nanoribbon,Current,Gold,Spin,Substitution,area:graphene}, area = {graphene} doi = {10.1016/j.physleta.2014.12.047}, }  Shintaro Fujii, Tomofumi Tada, Yuki Komoto, Takafumi Osuga, Takashi Murase, Makoto Fujita & Manabu Kiguchi, Rectifying Electron-Transport Properties through Stacks of Aromatic Molecules Inserted into a Self-Assembled Cage, Journal of the American Chemical Society, Vol. 137(18), pp. 5939--5947 (2015) area:molecular electronics molecular electronics Abstract: Aromatic stacks formed through self-assembly are promising building blocks for the construction of molecular electronic devices with adjustable electronic functions, in which noncovalently bound pi-stacks act as replaceable modular components. Here we describe the electron-transport properties of single-molecule aromatic stacks aligned in a self-assembled cage, using scanning probe microscopic and break junction methods. Same and different modular aromatic pairs are noncovalently bound and stacked within the molecular cage holder, which leads to diverse electronic functions. The insertion of same pairs induces high electronic conductivity (10(-3)-10(-2) G0, G0 = 2e(2)/h), while different pairs develop additional electronic rectification properties. The rectification ratio was, respectively, estimated to be 1.4-2 and textgreater10 in current-voltage characteristics and molecular orientation-dependent conductance measurements at a fixed bias voltage. Theoretical calculations demonstrate that this rectification behavior originates from the distinct stacking order of the internal aromatic components against the electron-transport direction and the corresponding lowest unoccupied molecular orbital conduction channels localized on one side of the molecular junctions. BibTeX: @article{Fujii2015, title = {Rectifying Electron-Transport Properties through Stacks of Aromatic Molecules Inserted into a Self-Assembled Cage}, author = {Fujii, Shintaro and Tada, Tomofumi and Komoto, Yuki and Osuga, Takafumi and Murase, Takashi and Fujita, Makoto and Kiguchi, Manabu}, journal = {Journal of the American Chemical Society}, volume = {137}, number = {18}, pages = {5939--5947}, year = {2015}, keywords = {area:molecular electronics}, area = {molecular electronics} doi = {10.1021/jacs.5b00086}, }  Wenjiang Liu, Shaohong Cai & Xiaoqing Deng, Rectifying Performance and Negative Differential Resistance Behavior of Doping Atoms Effect in Polyphenyls, Journal of Electronic Materials, Vol. 44(2), pp. 667--674 (2015) Rectifying,area:molecular electronics,doping,molecular electronics,negative differential resistance molecular electronics Abstract: The properties of two polyphenyls doped with nitrogen and boron atoms, which are connected by an alkane chain, are investigated by the non-equilibrium Green's function method combined with the density functional theory. It has been found that the doped sites have significant effects on the current-voltage characteristics. For models with the N(B) near the alkane chain, the rectification ratio is smaller, but the rectifying performance of models with the N(B) far away from the alkane chain is tremendously enhanced and rectification ratios can reach 280, alongside negative differential resistance behavior. The mechanisms for these phenomena are explained by transmission spectra, the molecular projected self-consistent Hamiltonian eigenstates, electrostatic potential distribution, and projected density of states. BibTeX: @article{Liu2015d, title = {Rectifying Performance and Negative Differential Resistance Behavior of Doping Atoms Effect in Polyphenyls}, author = {Liu, Wenjiang and Cai, Shaohong and Deng, Xiaoqing}, journal = {Journal of Electronic Materials}, publisher = {Springer US}, volume = {44}, number = {2}, pages = {667--674}, year = {2015}, keywords = {Rectifying,area:molecular electronics,doping,molecular electronics,negative differential resistance}, area = {molecular electronics} doi = {10.1007/s11664-014-3563-x}, }  J. Li, J. Hu, H. Wang & R.Q. Wu, Rhenium-phthalocyanine molecular nanojunction with high magnetic anisotropy and high spin filtering efficiency, Applied Physics Letters, Vol. 107 pp. 032404 (2015) Electrodes,Gold,Magnetic anisotropy,Spintronic devices,Transport properties,area:molecular electronics molecular electronics Abstract: Using the density functional and non-equilibrium Green's function approaches, we studied the magnetic anisotropy and spin-filtering properties of various transition metal-Phthalocyanine molecular junctions across two Auelectrodes. Our important finding is that the Au-RePc-Au junction has both large spin filtering efficiency (textgreater80%) and large magnetic anisotropy energy, which makes it suitable for device applications. To provide insights for the further experimental work, we discussed the correlation between the transport property,magnetic anisotropy, and wave function features of the RePc molecule, and we also illustrated the possibility of controlling its magnetic state. BibTeX: @article{Li2015b, title = {Rhenium-phthalocyanine molecular nanojunction with high magnetic anisotropy and high spin filtering efficiency}, author = {Li, J. and Hu, J. and Wang, H. and Wu, R. Q.}, journal = {Applied Physics Letters}, volume = {107}, pages = {032404}, year = {2015}, keywords = {Electrodes,Gold,Magnetic anisotropy,Spintronic devices,Transport properties,area:molecular electronics}, area = {molecular electronics} doi = {10.1063/1.4927146}, }  Yedilfana S. Mekonnen, Juan M. Garcia-Lastra, Jens S. Hummelshøj, Chengjun Jin & Tejs Vegge, Role of Li2O2@Li2CO3 Interfaces on Charge Transport in Nonaqueous Li-Air Batteries, Journal of Physical Chemistry C, Vol. 119(32), pp. 18066--18073 (2015) CARBONATE,ELECTRONIC-STRUCTURE,LI-O-2 BATTERIES,LI2CO3,LI2O2,LITHIUM PEROXIDE,area:battery,area:interfaces battery,interfaces Abstract: The formation and oxidation of the main discharge product in nonaqueous secondary Li?O2 batteries, that is, Li2O2, has been studied intensively, but less attention has been given to the formation of cathode?electrolyte interfaces, which can significantly influence the performance of the Li?O2 battery. Here we apply density functional theory with the Hubbard U correction (DFT+U) and nonequilibrium Green?s function (NEGF) methods to investigate the role of Li2O2@Li2CO3 interface layers on the ionic and electronic transport properties at the oxygen electrode. We show that, for example, lithium vacancies accumulate at the peroxide part of the interface during charge, reducing the coherent electron transport by two to three orders of magnitude compared with pristine Li2O2. During discharge, Li2O2@Li2CO3 interfaces may, however, provide an alternative in-plane channel for fast electron polaron hopping that could improve the electronic conductivity and ultimately increase the practical capacity in nonaqueous Li?O2 batteries. BibTeX: @article{Mekonnen2015, title = {Role of Li2O2@Li2CO3 Interfaces on Charge Transport in Nonaqueous Li-Air Batteries}, author = {Mekonnen, Yedilfana S. and Garcia-Lastra, Juan M. and Hummelshøj, Jens S. and Jin, Chengjun and Vegge, Tejs}, journal = {Journal of Physical Chemistry C}, volume = {119}, number = {32}, pages = {18066--18073}, year = {2015}, keywords = {CARBONATE,ELECTRONIC-STRUCTURE,LI-O-2 BATTERIES,LI2CO3,LI2O2,LITHIUM PEROXIDE,area:battery,area:interfaces}, area = {battery,interfaces} doi = {10.1021/acs.jpcc.5b04432}, }  C. Preferencial Kala, P. Aruna Priya & D. John Thiruvadigal, Role of side groups and temperature dependent studies in a molecular device, Journal of Computational Electronics, Vol. 14(1), pp. 240--248 (2015) Extended Huckel theory (EHT),Molecular electronics,Non-equlibrium Green's function (NEGF),Quantum transport,area:molecular electronics,negative differential resistance molecular electronics Abstract: The quantum transport through Tour Wires (TWs) functionalized with different side groups was studied using nonequilibrium Green's function formalism combined with extended Huckel theory. Au-TW-Au junctions were constructed with functional groups NO2 and NH2. The transmission spectrum and the isosurface of transmission eigen channel at the HOMO resonance and the LUMO resonance shows that the resonant transmission peaks are related to the delocalized nature of the π-orbitals of the TWs that was not much affected by the functionalization at room temperature. Furthermore, the influence of the temperature effect on the transport characteristics have been emphasized, and the result shows that for the TW and TW-NH2 systems conductance increase with increasing temperature indicating the dominating transport mechanism which is due to thermionic emission. The temperature dependence arises from the thermal spreading in the leads but also from a thermal average over the different configurations. In particular, negative differential resistance nature was observed for TW-NO2 at the temperature of 100 K in the positive and the negative bias region. BibTeX: @article{Kala2015, title = {Role of side groups and temperature dependent studies in a molecular device}, author = {Kala, C Preferencial and Aruna Priya, P and John Thiruvadigal, D}, journal = {Journal of Computational Electronics}, publisher = {Springer US}, volume = {14}, number = {1}, pages = {240--248}, year = {2015}, keywords = {Extended Huckel theory (EHT),Molecular electronics,Non-equlibrium Green's function (NEGF),Quantum transport,area:molecular electronics,negative differential resistance}, area = {molecular electronics} doi = {10.1007/s10825-014-0644-2}, }  S. Barzilai, F. Tavazza & L.E. Levine, Sensitivity of gold nano-conductors to voids, substitutions, and electric field: ab initio results, Journal of Materials Science, Vol. 50(1), pp. 412--419 (2015) Au,area:nanowires,gold,nano conductor,nanowires nanowires Abstract: Gold nanowires are good candidates for nano-electronics devices. A previous study has shown that the beryllium-terminated BeO (0001) surface may be a useful platform for supporting gold nano-conductors, since it preserves the nano wire configuration and does not restrict its conductivity. Here, we used ab initio simulations to determine the sensitivity of potential gold nano-conductors to the presence of point defects, O2 substitutions and to an applied perpendicular electric field, as in field effect transistors. We found that the presence of the point defects causes only small changes in the atomic bond lengths of the NW, does not alter the NW configuration, but may affect the overall conductivity. Single or double voids on the same channel reduce the conductance by 28 % at most, but when the voids arrange in a way that only one channel remains for conductance, it reduces by factor of two to  1 G0 (G0 = 2e 2/h). The presence of a single O2 molecule as a substitution reduces the electron availability in the neighboring Au atoms, in most cases reducing the conductance. The perpendicular electric field, which is typical for field effect transistors, affects the electron density distribution, shifts and changes the conductance spectra profile, but does not decrease the conductivity. BibTeX: @article{Barzilai2015, title = {Sensitivity of gold nano-conductors to voids, substitutions, and electric field: ab initio results}, author = {Barzilai, S and Tavazza, F and Levine, L E}, journal = {Journal of Materials Science}, publisher = {Springer US}, volume = {50}, number = {1}, pages = {412--419}, year = {2015}, keywords = {Au,area:nanowires,gold,nano conductor,nanowires}, area = {nanowires} doi = {10.1007/s10853-014-8600-x}, }  Yukihito Matsuura, Spin conduction in nitroxide molecules, Chemical Physics Letters, Vol. 619 pp. 23--26 (2015) area:molecular electronics,area:spintronics,nitroxide radical,spin conduction molecular electronics,spintronics Abstract: Spin conduction by a molecule-containing nitroxide radicals linked via a phenylene coupling unit was estimated by calculating the transmission of electrons in the molecule when sandwiched between two semi-infinite periodic gold crystals. Nitroxides linked via a m-phenylene coupling unit showed a large splitting in the energy of the transmission peaks of alpha;- and beta;-spins, whereas this energy splitting was smaller for molecules with extended π-conjugation, such as nitroxides linked via a p-phenylene coupling unit. The energy splitting of transmission is influenced by spin polarization and constructive/destructive interference of radicals through the phenylene coupling unit. BibTeX: @article{Matsuur2015, title = {Spin conduction in nitroxide molecules}, author = {Matsuura, Yukihito}, journal = {Chemical Physics Letters}, volume = {619}, pages = {23--26}, year = {2015}, keywords = {area:molecular electronics,area:spintronics,nitroxide radical,spin conduction}, area = {molecular electronics,spintronics} doi = {10.1016/j.cplett.2014.11.030}, }  C.H. Yang, X.Q. Deng, G.P. Tang & Z.Q. Fan, Spin filtering behaviors for a carbon chain connected with armchair- and zigzag-edged graphene nanoribbon electrodes, Solid State Communications, Vol. 203 pp. 26--30 (2015) Carbon chain,First-principles calculation,Graphene,Spin filtering,area:spintronics spintronics Abstract: Using the non-equilibrium Green's function method combined with the density functional theory, we investigate the spin transport properties of carbon chains connected with armchair- and zigzag-edged graphene nanoribbon (ZGNR) electrodes at finite bias with the parallel magnetism configuration. When spin polarized electrons are injected into carbon chains from the ZGNR electrode, the beta;-spin current is nearly zero, while the α-spin current shows large values in the calculated bias region, thus the spin polarization 100% can be achieved, which is a promising pathway for developing a spin filter. BibTeX: @article{Yang2015, title = {Spin filtering behaviors for a carbon chain connected with armchair- and zigzag-edged graphene nanoribbon electrodes}, author = {Yang, C H and Deng, X Q and Tang, G P and Fan, Z Q}, journal = {Solid State Communications}, volume = {203}, pages = {26--30}, year = {2015}, keywords = {Carbon chain,First-principles calculation,Graphene,Spin filtering,area:spintronics}, area = {spintronics} doi = {10.1016/j.ssc.2014.10.033}, }  Q.H. Wu, P. Zhao, Y. Su, S.J. Li, J.H. Guo & G. Chen, Spin transport of dibenzotetraaza[14]annulene complexes with first row transition metals, RSC Adv., Vol. 5(65), pp. 52938--52944 (2015) MPSH,area:molecular electronics,area:spin molecular electronics,spin Abstract: Based on spin-polarized first-principles density functional theory in conjunction with the nonequilibrium Green's function method, the spin transport properties of transition metal (TM)-dibenzotetraaza[14]annulene (DBTAA) complexes (TM = Ti, V, Cr, Mn, Fe, Co, Ni, and Cu) sandwiched between two Au electrodes are investigated. The results show that Fe- and Co-DBTAA can display perfect spin filtering behavior in a wide bias voltage region. Moreover, it is found that the connected position of anchoring groups on the complexes affect significantly the spin filtering efficiency. The observed spin filtering behavior is explained by the spin-resolved transmission spectrum and molecular projected self-consistent Hamiltonian state analyses. BibTeX: @article{Wu2015e, title = {Spin transport of dibenzotetraaza[14]annulene complexes with first row transition metals}, author = {Wu, Q H and Zhao, P and Su, Y and Li, S J and Guo, J H and Chen, G}, journal = {RSC Adv.}, publisher = {The Royal Society of Chemistry}, volume = {5}, number = {65}, pages = {52938--52944}, year = {2015}, keywords = {MPSH,area:molecular electronics,area:spin}, area = {molecular electronics,spin} doi = {10.1039/C5RA07456H}, }  Dongqing Zou, Bin Cui, Xiangru Kong, Wenkai Zhao, Jingfen Zhao & Desheng Liu, Spin transport properties in lower n-acene-graphene nanojunctions, Phys. Chem. Chem. Phys., Vol. 17(17), pp. 11292--11300 (2015) GROUND-STATES,LAYER GRAPHENE,M,ROOM-TEMPERATURE,area:graphene,area:molecular electronics graphene,molecular electronics Abstract: A series of n-acene-graphene (n = 3, 4, 5, 6) devices, in which n-acene molecules are sandwiched between two zigzag graphene nanoribbon (ZGNR) electrodes, are modeled through the spin polarized density functional theory combined with the non-equilibrium Green's function technique. Our theoretical results show that for n-acene molecules ranging from anthracene to hexacene, the spin-polarized electronic states near the Fermi level can be induced by the spin-polarized ZGNR electrodes, which strengthen gradually to facilitate the electronic transport. A nearly 100% spin filtering ratio and a dualorientation spin-rectifying effect are observed in a wide range of bias voltage. Importantly, an over 8000% giant magnetoresistance is obtained in the low bias range from -0.1 V to +0.1V. Moreover, negative differential resistance behaviors are detected in these devices. The potential mechanisms of these intriguing phenomena are proposed and these findings would be instructive for the design and synthesis of high-performance graphene-based spin-related devices. BibTeX: @article{Zou2015b, title = {Spin transport properties in lower n-acene-graphene nanojunctions}, author = {Zou, Dongqing and Cui, Bin and Kong, Xiangru and Zhao, Wenkai and Zhao, Jingfen and Liu, Desheng}, journal = {Phys. Chem. Chem. Phys.}, publisher = {The Royal Society of Chemistry}, volume = {17}, number = {17}, pages = {11292--11300}, year = {2015}, keywords = {GROUND-STATES,LAYER GRAPHENE,M,ROOM-TEMPERATURE,area:graphene,area:molecular electronics}, area = {graphene,molecular electronics} doi = {10.1039/C5CP00544B}, }  Yipeng An, Mengjun Zhang, Lipeng Chen, Congxin Xia, Tianxing Wang, Zhaoming Fu, Zhaoyong Jiao & Guoliang Xu, Spin-dependent electronic transport properties of zigzag silicon carbon nanoribbon, RSC Adv., Vol. 5(129), pp. 107136--107141 (2015) CONDUCTANCE,GRAPHENE,area:2dmat,area:spin 2dmat,spin Abstract: Spin-dependent electronic transport properties of the zigzag silicon carbon nanoribbon (Z-SiCNR) are studied by employing the non-equilibrium Green's function method in the framework of density functional theory. It is found that the Z-SiCNR exhibits a variety of exotic physical properties. While the Z-SiCNR in the metallic FM state presents spin filtering and current-limited effects, it is shown that the abnormal oscillation of spin-polarized currents with spin polarization as high as 100% under a certain bias voltage emerges in the half-metallic AFM state. The results demonstrate that tuning the spin state of the zigzag SiC nanoribbon provides a possible avenue to design next generation spin nanodevices with novel functionalities. BibTeX: @article{An2015a, title = {Spin-dependent electronic transport properties of zigzag silicon carbon nanoribbon}, author = {An, Yipeng and Zhang, Mengjun and Chen, Lipeng and Xia, Congxin and Wang, Tianxing and Fu, Zhaoming and Jiao, Zhaoyong and Xu, Guoliang}, journal = {RSC Adv.}, publisher = {Royal Society of Chemistry}, volume = {5}, number = {129}, pages = {107136--107141}, year = {2015}, keywords = {CONDUCTANCE,GRAPHENE,area:2dmat,area:spin}, area = {2dmat,spin} doi = {10.1039/C5RA24276B}, }  Hui Fang, Fei-Peng Zhang, Zhi-Nian Jiang, Jin-Yun Peng & Ru-Zhi Wang, Strain-induced asymmetric modulation of band gap in narrow armchair-edge graphene nanoribbon, Modern Physics Letters B, Vol. 29(34), pp. 1550224 (2015) Graphene nanoribbon (GNR),area:graphene,band gap,electronic structure,strain graphene Abstract: We investigate the band structure of narrow armchair-edge graphene nanoribbons (AGNRs) under tensile strain by means of an extension of the Extended Hückel method. The strain-induced band gap modulation presents asymmetric behavior. The asymmetric modulation of band gap is derived from the different changes of conduction and valence bands near Fermi level under tensile strain. Further analysis suggests that the asymmetric variation of band structure near Fermi level only appear in narrow armchair-edge graphene nanoribbons. BibTeX: @article{Fang2015, title = {Strain-induced asymmetric modulation of band gap in narrow armchair-edge graphene nanoribbon}, author = {Fang, Hui and Zhang, Fei-Peng and Jiang, Zhi-Nian and Peng, Jin-Yun and Wang, Ru-Zhi}, journal = {Modern Physics Letters B}, volume = {29}, number = {34}, pages = {1550224}, year = {2015}, keywords = {Graphene nanoribbon (GNR),area:graphene,band gap,electronic structure,strain}, area = {graphene} doi = {10.1142/S0217984915502243}, }  Santosh Kumar Gupta & Girija Nandan Jaiswal, Study of Nitrogen terminated doped zigzag GNR FET exhibiting negative differential resistance, Superlattices and Microstructures, Vol. 86 pp. 355--362 (2015) Graphene,High-k dielectric,Negative differential resistance,Zigzag GNR FET,area:2dmat,area:graphene 2dmat,graphene Abstract: This paper presents the study of Gallium and Aluminum doped Nitrogen terminated zigzag Graphene Nano Ribbon (GNR) FET with high-k dielectric. The GNR FET structure has been designed and simulated using Quantumwise Atomistix Toolkit software package. The presented GNR FET with n-type (Nitrogen doped) electrodes and p-type (Gallium or Aluminum doped) scattering region are simulated and analyzed using Density Functional Theory combined with NEGF formalism and Device Density of States (DDOS). The device shows a negative differential resistance phenomenon which can be controlled by the gate of the zigzag GNR FET. It is found that doping of Gallium and Aluminum in scattering region provides higher drain current, higher ION/IOFF and IP/IV ratios as compared to that of Boron doped zigzag GNR FET. The potential applications of the device are in logical, high frequency, and memory devices. BibTeX: @article{Gupta2015, title = {Study of Nitrogen terminated doped zigzag GNR FET exhibiting negative differential resistance}, author = {Gupta, Santosh Kumar and Jaiswal, Girija Nandan}, journal = {Superlattices and Microstructures}, publisher = {Elsevier Ltd}, volume = {86}, pages = {355--362}, year = {2015}, keywords = {Graphene,High-k dielectric,Negative differential resistance,Zigzag GNR FET,area:2dmat,area:graphene}, area = {2dmat,graphene} doi = {10.1016/j.spmi.2015.07.069}, }  Can Cao, Mengqiu Long & Xiancheng Mao, Symmetry-Dependent Spin Transport Properties and Spin-Filter Effects in Zigzag-Edged Germanene Nanoribbons, Journal of Nanomaterials, Vol. 2015 pp. 810659 (2015) area:2dmat 2dmat Abstract: We performed the first-principles calculations to investigate the spin-dependent electronic transport properties of zigzag-edged germanium nanoribbons (ZGeNRs). We choose of ZGeNRs with odd and even widths of 5 and 6, and the symmetry-dependent transport properties have been found, although the ? mirror plane is absent in ZGeNRs. Furthermore, even-? and odd-? ZGeNRs have very different current-voltage relationships. We find that the even 6-ZGeNR shows a dual spin-filter effect in antiparallel (AP) magnetism configuration, but the odd 5-ZGeNR behaves as conventional conductors with linear current-voltage dependence. It is found that when the two electrodes are in parallel configuration, the 6-ZGeNR system is in a low resistance state, while it can switch to a much higher resistance state when the electrodes are in AP configuration, and the magnetoresistance of 270% can be observed. BibTeX: @article{Cao2015a, title = {Symmetry-Dependent Spin Transport Properties and Spin-Filter Effects in Zigzag-Edged Germanene Nanoribbons}, author = {Cao, Can and Long, Mengqiu and Mao, Xiancheng}, journal = {Journal of Nanomaterials}, volume = {2015}, pages = {810659}, year = {2015}, keywords = {area:2dmat}, area = {2dmat} doi = {10.1155/2015/810659}, }  X.Q. Deng, Z.H. Zhang, G.P. Tang, Z.Q. Fan, C.H. Yang & L. Sun, The design of bipolar spin semiconductor based on zigzag-edge graphene nanoribbons, Carbon, Vol. 94 pp. 317--325 (2015) area:spin,nanoribbons spin Abstract: Using first-principle methods, we investigate the magnetism properties of zigzag-edge graphene nanoribbons (ZGNRs) with a nanopore, and find that edges of such a nanopore show important effects although the electron transport is mainly along the outer edge of ZGNR. The robust bipolar spin semiconductor can be obtained when the edges of such a nanopore are varied, where both spin states have a gap but can relatively shift. We speculate that bipolar spin semiconductor behavior is related with two factors: broken inner edge states and width of electrode. A series of models are considered: 6-ZGNRs with only one edge occupied by one triangle protrusion (TP), are connected with different width ZGNR electrodes. With the increase the electrode width along the TP edge direction, the systems show the following behavior in turn: spin metallicity, spin gapless semiconductor, and bipolar spin semiconductor. Finally, we show that the half-metallicity is realizable when electric fields are applied across the ZGNR with a nanopore, and their magnetic properties can be controlled by the external electric field. These findings suggest a new possibility for developing nanometer-scale carbon spintronic devices. BibTeX: @article{Deng2015a, title = {The design of bipolar spin semiconductor based on zigzag-edge graphene nanoribbons}, author = {Deng, X. Q. and Zhang, Z. H. and Tang, G. P. and Fan, Z. Q. and Yang, C. H. and Sun, L.}, journal = {Carbon}, publisher = {Elsevier Ltd}, volume = {94}, pages = {317--325}, year = {2015}, keywords = {area:spin,nanoribbons}, area = {spin} doi = {10.1016/j.carbon.2015.06.078}, }  Xiu Yan Liang, Guiling Zhang, Peng Sun, Yan Shang, Zhao-Di Yang & Xiao Cheng Zeng, The electronic and transport properties of (VBz)n@CNT and (VBz)n@BNNT nanocables, J. Mater. Chem. C, Vol. 3(16), pp. 4039--4049 (2015) BORON-NITRIDE NANOTUBES,POLYDECKER SANDWICH COMPO,area:nan nan Abstract: The electronic structures and transport properties of prototype carbon nanotube (CNT) (10,10) and boron-nitride nanotube (BNNT) (10,10) nanocables, including (VBz)(n)@CNT and (VBz)(n)@BNNT (where Bz = C6H6), are investigated using the density functional theory (DFT) and the non-equilibrium Green's function (NEGF) methods. It is found that (VBz)(n)@CNT shows a metallic character while (VBz)(n)@BNNT exhibits a half-metallic feature. Both (VBz)(n)@CNT and (VBz)(n)@BNNT nanocables show spin-polarized transport properties, namely, spin-down state gives rise to a higher conductivity than the spin-up state. For (VBz)(n)@CNT, the CNT sheath contributes the metallic transport channel in both spin-up and spin-down states, while the (VBz)(n) core is an effective transport path only in the spin-down state. For (VBz)(n)@BNNT, the BNNT sheath is an insulator in both spin-up and spin-down states. Hence, the transport properties of the (VBz)(n)@BNNT nanocable are attributed to the spin-down state of the (VBz)(n) core. The computed spin filter efficiency of (VBz)(n)@CNT is less than 50% within the bias of -1.0 to 1.0 V. In contrast, the spin filter efficiency of (VBz)(n)@BNNT can be greater than 90%, suggesting that the (VBz)(n)@BNNT nanocable is a very good candidate for a spin filter. Moreover, encapsulating (VBz)(n) nanowires into either CNTs or BNNTs can introduce magnetism and the computed Curie or Neel temperatures of both (VBz)(n)@CNT and (VBz)(n)@BNNT are higher than 2000 K. These novel electronic and transport properties of (VBz)(n)@CNT and (VBz)(n)@BNNT nanocables render them as potential nanoparts for nanoelectronic applications. BibTeX: @article{Liang2015, title = {The electronic and transport properties of (VBz)n@CNT and (VBz)n@BNNT nanocables}, author = {Liang, Xiu Yan and Zhang, Guiling and Sun, Peng and Shang, Yan and Yang, Zhao-Di and Zeng, Xiao Cheng}, journal = {J. Mater. Chem. C}, publisher = {The Royal Society of Chemistry}, volume = {3}, number = {16}, pages = {4039--4049}, year = {2015}, keywords = {BORON-NITRIDE NANOTUBES,POLYDECKER SANDWICH COMPO,area:nan}, area = {nan} doi = {10.1039/C5TC00332F}, }  Yipeng An, Tianxing Wang, Zhaoming Fu, Xingli Chu & Guoliang Xu, The electronic transport properties of graphene-like beryllium sulfide nanoribbons, Physics Letters A, Vol. 379(32-33), pp. 1837--1841 (2015) Charge transport,First-principl,Nano electronics,area:2dmat 2dmat Abstract: The electronic transport properties of zigzag beryllium sulfide nanoribbons (ZBeSNRs) are investigated by first-principles calculations. The results indicate that the electrons flow mainly through the two edges of ZBeSNRs. The electron transmission pathways are analyzed in detail. The ZBeSNRs show the remarkable negative differential resistance (NDR) properties, which are independent of the nanoribbon width due to their very similar band structures. The NDR behavior can be maintained by introducing a Be or S atom vacancy defect. The H-passivated ZBeSNR presents the interesting current-limited effect. The ZBeSNRs could be the promising candidates for the future nano devices, such as NDR devices. BibTeX: @article{An2015, title = {The electronic transport properties of graphene-like beryllium sulfide nanoribbons}, author = {An, Yipeng and Wang, Tianxing and Fu, Zhaoming and Chu, Xingli and Xu, Guoliang}, journal = {Physics Letters A}, volume = {379}, number = {32-33}, pages = {1837--1841}, year = {2015}, keywords = {Charge transport,First-principl,Nano electronics,area:2dmat}, area = {2dmat} doi = {10.1016/j.physleta.2015.05.013}, }  S. Caliskan & S. Guner, The role of Co atoms in spin dependent electronic properties of graphite-like ZnO structures, Journal of Magnetism and Magnetic Materials, Vol. 373 pp. 96--102 (2015) Density functional theory,Density of state,Doped ZnO,First principles,area:2dmat,area:spintronics 2dmat,spintronics Abstract: A first principles study is employed to reveal the electronic properties of graphite-like Co doped ZnO structures composed of atomic layers when spin property of electrons is involved. The influence of Co atoms, which are substituting the Zn atoms, was addressed through distinct atomic arrangements formed by specific atomic configurations and various Co concentrations. We obtained that the spin dependent behavior is largely determined by the atomic arrangement which can crucially impact the electronic structure for a certain spin orientation. It was observed that atomic configuration is an essential factor which may reduce or enhance the minority-spin energy gap relative to majority one. It was shown that the emerging spin polarization can be manipulated by the atomic arrangement of the layered structures. Both the spin polarization and the magnetic moment were found to be contributed by both Co and O atoms. The stability of a system via formation energy, the role of Co dopants positioned at different Zn sites, the number of both Co atoms and layers in a supercell, and the mechanisms governing the spin dependent behavior of these structures are discussed. BibTeX: @article{Caliskan2015b, title = {The role of Co atoms in spin dependent electronic properties of graphite-like ZnO structures}, author = {Caliskan, S and Guner, S}, journal = {Journal of Magnetism and Magnetic Materials}, volume = {373}, pages = {96--102}, year = {2015}, keywords = {Density functional theory,Density of state,Doped ZnO,First principles,area:2dmat,area:spintronics}, area = {2dmat,spintronics} doi = {10.1016/j.jmmm.2014.05.039}, }  Anuja Chanana & Santanu Mahapatra, Theoretical Insights to Niobium-Doped Monolayer MoS2-Gold Contact, IEEE Transactions on Electron Devices, Vol. 62(7), pp. 2346--2351 (2015) MoS2,Schottky barrier,TMD,area:graphene,area:interfaces,doping,niobium graphene,interfaces Abstract: We report a first principles study of the electronic properties for a contact formed between Nb-doped monolayer MoS2 and gold for different doping concentrations. We first focus on the shift of energy levels in band structure and the density of states with respect to the Fermi level for a geometrically optimized 5x5 MoS2 supercell for both pristine and Nb-doped structures. The doping is achieved by substituting Mo atoms with Nb atoms at random positions. It is observed that for an experimentally reported sheet hole doping concentration of (1.8)10^14 cm^-2, the pristine MoS2 converts to degenerate p-type semiconductor. Next, we interface this supercell with six layers of (111) cleaved surface of gold to investigate the contact nature of MoS2-Au system. By careful examination of projected band structure, projected density of states, effective potential and charge density difference, we demonstrate that the Schottky barrier nature observed for pure MoS2-Au contact can be converted from n-type to p-type by efficient Nb doping. BibTeX: @article{Chanana2015, title = {Theoretical Insights to Niobium-Doped Monolayer MoS2-Gold Contact}, author = {Chanana, Anuja and Mahapatra, Santanu}, journal = {IEEE Transactions on Electron Devices}, publisher = {Institute of Electrical & Electronics Engineers (IEEE)}, volume = {62}, number = {7}, pages = {2346--2351}, year = {2015}, keywords = {MoS2,Schottky barrier,TMD,area:graphene,area:interfaces,doping,niobium}, area = {graphene,interfaces} doi = {10.1109/ted.2015.2433931}, }  G.R. Berdiyorov, H. Bahlouli & F.M. Peeters, Theoretical study of electronic transport properties of a graphene-silicene bilayer, Journal of Applied Physics, Vol. 117(22), pp. 225101 (2015) Density functional theory,Fermi levels,Graphene,Silicon,Transport properties,area:graphene,area:interfaces graphene,interfaces Abstract: Electronic transport properties of a graphene-silicene bilayer system are studied using density-functional theory in combination with the nonequilibrium Green's function formalism. Depending on the energy of the electrons, the transmission can be larger in this system as compared to the sum of the transmissions of separated graphene and silicene monolayers. This effect is related to the increased electron density of states in the bilayer sample. At some energies, the electronic states become localized in one of the layers, resulting in the suppression of the electron transmission. The effect of an applied voltage on the transmission becomes more pronounced in the layered sample as compared to graphene due to the larger variation of the electrostatic potential profile. Our findings will be useful when creating hybrid nanoscale devices where enhanced transport properties will be desirable. BibTeX: @article{Berdiyorov2015a, title = {Theoretical study of electronic transport properties of a graphene-silicene bilayer}, author = {Berdiyorov, G. R. and Bahlouli, H. and Peeters, F. M.}, journal = {Journal of Applied Physics}, volume = {117}, number = {22}, pages = {225101}, year = {2015}, keywords = {Density functional theory,Fermi levels,Graphene,Silicon,Transport properties,area:graphene,area:interfaces}, area = {graphene,interfaces} doi = {10.1063/1.4921877}, }  Qiuhua Wu, Peng Zhao, Yan Su, Desheng Liu & Gang Chen, Thermal spin transport of a nitroxide radical-based molecule, RSC Adv., Vol. 5(27), pp. 20699--20703 (2015) CALORITRONICS,CONDUCTANCE,EFFICIENT THERMOELECTRIC-MATERIAL,FUTURE,GOLD,SILICON,SPINTRONICS,SURFACES,area:molecular electronics molecular electronics Abstract: Based on spin-polarized first-principles density functional theory combined with nonequilibrium Green's function method, the thermal spin transport properties of a nitroxide radical-based molecule sandwiched between two Au electrodes are investigated. The results show that opposite spin currents can be induced by applying a temperature difference, rather than bias voltage, between two electrodes. Moreover, a pure spin current and a completely spin-polarized current can be realized by tuning the transverse gate voltage. These results indicate that the nitroxide radical-based molecule is a potential material for spin caloritronic and spintronic applications. BibTeX: @article{Wu2015, title = {Thermal spin transport of a nitroxide radical-based molecule}, author = {Wu, Qiuhua and Zhao, Peng and Su, Yan and Liu, Desheng and Chen, Gang}, journal = {RSC Adv.}, publisher = {Royal Society of Chemistry (RSC)}, volume = {5}, number = {27}, pages = {20699--20703}, year = {2015}, keywords = {CALORITRONICS,CONDUCTANCE,EFFICIENT THERMOELECTRIC-MATERIAL,FUTURE,GOLD,SILICON,SPINTRONICS,SURFACES,area:molecular electronics}, area = {molecular electronics} doi = {10.1039/C4RA16845C}, }  G.P. Tang, Z.H. Zhang, X.Q. Deng, Z.Q. Fan & H.L. Zhu, Tuning spin polarization and spin transport of zigzag graphene nanoribbons by line defects, Physical Chemistry Chemical Physics, Vol. 17(1), pp. 638--643 (2015) Curie temperature,antiferromagnetism,area:graphene,area:spintronics,defects,ferrimagnetism,ferromagnetism,graphene nanoribbon,spin filter,spin transport graphene,spintronics Abstract: From first-principles methods, the spin-dependent electronic properties of zigzag-edged graphene nanoribbons (ZGNRs) with a line defect (558-defect) are investigated systematically and compared to those of the pristine ZGNR. Results show that the line defect possesses an obvious tuning effect on the spin-polarization of the edge carbon atoms of the defective ZGNRs, and the spin-polarization and spin-transport are sensitive to the position of line defects. The defective ZGNRs can realize a transition from antiferromagnetism (AFM) to ferrimagnetism and ferromagnetism (FM) via changing the position of line defects from the center to the zigzag edge of ZGNRs. More importantly, when the line defect is located at the one edge, the defective ZGNRs exhibit the long-range magnetic ordering at edges with a high Curie temperature up to 276 K, and the defective ZGNR system can generate a high-performance spin-filter effect in the large bias range, 0.0-0.5 V. Such a sensitive modulation for the spin-polarization and spin-transport holds great promise for applications of the graphene-based systems in nano-scale spintronic devices. BibTeX: @article{Tang2015, title = {Tuning spin polarization and spin transport of zigzag graphene nanoribbons by line defects}, author = {Tang, G P and Zhang, Z H and Deng, X Q and Fan, Z Q and Zhu, H L}, journal = {Physical Chemistry Chemical Physics}, publisher = {The Royal Society of Chemistry}, volume = {17}, number = {1}, pages = {638--643}, year = {2015}, keywords = {Curie temperature,antiferromagnetism,area:graphene,area:spintronics,defects,ferrimagnetism,ferromagnetism,graphene nanoribbon,spin filter,spin transport}, area = {graphene,spintronics} doi = {10.1039/C4CP03837A}, }  Anurag Srivastava, Md Shahzad Khan, Sanjeev Kumar Gupta & Ravindra Pandey, Unique electron transport in ultrathin black phosphorene: Ab-initio study, Applied Surface Science, Vol. 356 pp. 881--887 (2015) Ab-initio,Band structure,Black phosphorene,Electronic transport,Optical properties,Sensor,area:2dmat 2dmat Abstract: We present first principle structural, electronic, optical and transport analysis of black phosphorene a 2D layered material. The studied configuration shows semiconducting nature and the states around the Fermi energy are mainly contributed by the p-orbitals of atoms. In optical properties, the reflective spectrum is approximately dispersed in visible range suggesting that this 2D-nanostructure can be considered as shielding for visible region. Due to the anisotropy of the electronic structure of black phosphorene, the device performance is subtaintially preferable in armchair direction. Zero-bias transmission shows no conductance channel near Fermi level but in far region prominent spectra for the same is observed for black-phospherene. The studied configurations show non-linear current-voltage (I-V) characteristics. The sensitivity for NH3 and NO2 gas molecule is explored using electronic and current-voltage (I-V) characteristics. Investigations show that the black phosphorene has strong affinity for electron seeking NO2 molecule, thus providing an opportunity for its sensor application. BibTeX: @article{Srivastava2015b, title = {Unique electron transport in ultrathin black phosphorene: Ab-initio study}, author = {Srivastava, Anurag and Khan, Md Shahzad and Gupta, Sanjeev Kumar and Pandey, Ravindra}, journal = {Applied Surface Science}, publisher = {Elsevier B.V.}, volume = {356}, pages = {881--887}, year = {2015}, keywords = {Ab-initio,Band structure,Black phosphorene,Electronic transport,Optical properties,Sensor,area:2dmat}, area = {2dmat} doi = {10.1016/j.apsusc.2015.08.109}, }  Serhan Yamacli, Voltage-Dependent Electronic Transport Properties of Reduced Graphene Oxide with Various Coverage Ratios, Nano-Micro Letters, Vol. 7(1), pp. 42--50 (2015) Coverage ratio,Negative differential resistance,Reduced graphene oxide,area:graphene graphene Abstract: Graphene is mainly implemented by these methods: exfoliating, unzipping of carbon nanotubes, chemical vapour deposition, epitaxial growth and the reduction of graphene oxide. The latter option has the advantage of low cost and precision. However, reduced graphene oxide (rGO) contains hydrogen and/or oxygen atoms hence the structure and properties of the rGO and intrinsic graphene are different. Considering the advantages of the implementation and utilization of rGO, voltage-dependent electronic transport properties of several rGO samples with various coverage ratios are investigated in this work. Ab initio simulations based on density functional theory combined with non-equilibrium Green's function formalism are used to obtain the current-voltage characteristics and the voltage-dependent transmission spectra of rGO samples. It is shown that the transport properties of rGO are strongly dependent on the coverage ratio. Obtained results indicate that some of the rGO samples have negative differential resistance characteristics while normally insulating rGO can behave as conducting beyond a certain threshold voltage. The reasons of the peculiar electronic transport behaviour of rGO samples are further investigated, taking the transmission eigenstates and their localization degree into consideration. The findings of this study are expected to be helpful for engineering the characteristics of rGO structures. BibTeX: @article{Yamacli2015, title = {Voltage-Dependent Electronic Transport Properties of Reduced Graphene Oxide with Various Coverage Ratios}, author = {Yamacli, Serhan}, journal = {Nano-Micro Letters}, publisher = {Springer Berlin Heidelberg}, volume = {7}, number = {1}, pages = {42--50}, year = {2015}, keywords = {Coverage ratio,Negative differential resistance,Reduced graphene oxide,area:graphene}, area = {graphene} doi = {10.1007/s40820-014-0017-1}, }  Qiu-Hua Wu, Peng Zhao & De-Sheng Liu, A First-principles Study of Spin-polarized Transport Properties of a Co-coordination Complex, Chinese Phys. Lett., Vol. 31(6), pp. 67302 (2014) area:molecular electronics,area:spintronics,gold electrode,spintronics molecular electronics,spintronics Abstract: Based on non-equilibrium Green's function formalism and density functional theory calculations, we investigate the spin-polarized transport properties of a Co-coordination complex between two gold electrodes, in which a Co ion is trapped between two 4-mercaptopyridine molecules. Our results demonstrate that the transmission spectra of the system show distinctive features in the spin-up and spin-down channels. Moreover, the current-voltage curves confirm that the system can exhibit robust spin-filtering effect at finite bias voltage, giving the system potential in molecular spintronics applications. BibTeX: @article{Wu2014c, title = {A First-principles Study of Spin-polarized Transport Properties of a Co-coordination Complex}, author = {Wu, Qiu-Hua and Zhao, Peng and Liu, De-Sheng}, journal = {Chinese Phys. Lett.}, publisher = {IOP Publishing}, volume = {31}, number = {6}, pages = {67302}, year = {2014}, keywords = {area:molecular electronics,area:spintronics,gold electrode,spintronics}, area = {molecular electronics,spintronics} doi = {10.1088/0256-307x/31/6/067302}, }  P. Zhao, Q.H. Wu, H.Y. Liu, D.S. Liu & G. Chen, A first-principles study of the spin transport properties of a 4H-TAHDI-based multifunctional spintronic device with graphene nanoribbon electrodes, J. Mater. Chem. C, Vol. 2(32), pp. 6648 (2014) area:graphene,area:spintronics,graphene,nanoribbon,spin transport graphene,spintronics Abstract: By using the nonequilibrium Green's function formalism in combination with the density functional theory, we have investigated the spin transport properties of a 4H-TAHDI-based multifunctional spintronic device constructed by contacting a 4H-TAHDI molecule with two ferromagnetic zigzag-edge graphene nanoribbon electrodes. The results show that perfect giant magnetoresistance, spin-filtering, bipolar spin-rectifying, and negative differential resistance effects can be realized simultaneously. The mechanisms were proposed for these interesting phenomena. Our results demonstrate that this system holds promise in the design of a high-performance multifunctional single-molecule spintronic device. BibTeX: @article{Zhao2014c, title = {A first-principles study of the spin transport properties of a 4H-TAHDI-based multifunctional spintronic device with graphene nanoribbon electrodes}, author = {Zhao, P and Wu, Q H and Liu, H Y and Liu, D S and Chen, G}, journal = {J. Mater. Chem. C}, publisher = {Royal Society of Chemistry (RSC)}, volume = {2}, number = {32}, pages = {6648}, year = {2014}, keywords = {area:graphene,area:spintronics,graphene,nanoribbon,spin transport}, area = {graphene,spintronics} doi = {10.1039/c4tc00895b}, }  Faruque M. Hossain, Feras Al-Dirini & Efstratios Skafidas, A graphene nanoribbon neuro-sensor for glycine detection and imaging, Journal of Applied Physics, Vol. 115(21), pp. 214303 (2014) area:graphene,glycine,graphene,nanoribbon,sensor graphene Abstract: Glycine acts as a neurotransmitter in the Central Nervous System (CNS) and plays a vital role in processing of motor and sensory information that control movement, vision, and audition. Glycine detection and imaging can lead to a greater understanding of how this information is processed in the CNS. Here, we present a neuro-sensor for the detection and imaging of Glycine molecules, based on a zigzag Graphene Nanoribbon device structure. An energetically stable Nitrogen Vacancy (NV) center is introduced in the device to enable its use in neuronal imaging applications.We demonstrate, by using the Density Functional Theory and Nonequilibrium Green's Function method, that the device detects the attachment of a single Glycine molecule to its edges by significant changes in its conductance. The attachment of Glycine induces current channels around the NV center increasing the current flow through the device. In absence of Glycine, the presence of the NV center suppresses current flow through the device, significantly reducing its power consumption, and allowing for its use in proximity of living neuron cells. BibTeX: @article{Hossain2014, title = {A graphene nanoribbon neuro-sensor for glycine detection and imaging}, author = {Hossain, Faruque M and Al-Dirini, Feras and Skafidas, Efstratios}, journal = {Journal of Applied Physics}, volume = {115}, number = {21}, pages = {214303}, year = {2014}, keywords = {area:graphene,glycine,graphene,nanoribbon,sensor}, area = {graphene} doi = {10.1063/1.4880744}, }  Xiaobo Li, Hao Gao, Haiqing Wan, Hui-Li Li & Guanghui Zhou, A multi-functional molecular device based on oligo phenylenevinylene and graphene, Chemical Physics Letters, Vol. 610-611 pp. 298--302 (2014) area:molecular electronics,electronic transport,graphene,local density of states.,nanoribbon,negative differential resistance,oligo phenylenevinylene,spin diod,spin filtering,switching molecular electronics Abstract: Using ab initio method, we study the electronic transport for a molecular device consisting of an oligo(p-phenylenevinylene) (OPV) molecule sandwiched between two zigzag-edged graphene nanoribbon (ZGNR) electrodes. Interestingly, a number of electrical functions, including switching, spin-filtering, negative differential resistance and spin-diode, are numerically observed in the device with different OPV conformations respect to ZGNRs and spin configurations in two electrodes. By analyzing the spatial distribution of local density of states, the performance of spin-filtering and -rectifying is explained to the asymmetry distribution of the central molecular orbitals as well as the corresponding coupling to the electrodes. BibTeX: @article{Li2014c, title = {A multi-functional molecular device based on oligo phenylenevinylene and graphene}, author = {Li, Xiaobo and Gao, Hao and Wan, Haiqing and Li, Hui-Li and Zhou, Guanghui}, journal = {Chemical Physics Letters}, volume = {610-611}, pages = {298--302}, year = {2014}, keywords = {area:molecular electronics,electronic transport,graphene,local density of states.,nanoribbon,negative differential resistance,oligo phenylenevinylene,spin diod,spin filtering,switching}, area = {molecular electronics} doi = {10.1016/j.cplett.2014.07.055}, }  Bin Cui, Yuqing Xu, Guomin Ji, Hui Wang, Wenkai Zhao, Yaxin Zhai, Dongmei Li & Desheng Liu, A single-molecule diode with significant rectification and negative differential resistance behavior, Organic Electronics, Vol. 15(2), pp. 484--490 (2014) area:molecular electronics,doping,experimental comparison,gate modulation,non-equilibrium Green's function,rectification,unimolecular diode molecular electronics Abstract: A series of ferrocenylalkanethiol (HSCnFc) single molecular junctions are modeled and their rectification ratios (RRs) are up to 100 (for HSC11Fc), which agrees with the experiments of Whitesides et al. Not only explanation to the origin of the remarkable large RR is given, but also the reason why one order deviation of RR between HSC11Fc and HSC9Fc is discussed and depicted, which was not pointed out by previous researchers. The single asymmetric accessible molecular orbital (MO) model is evaluated, which is different from the Donor (D)-Acceptor (A) models reported before and a clear negative differential resistance (NDR) behavior is found and explained in the HSC11Fc based device. BibTeX: @article{Cui2014b, title = {A single-molecule diode with significant rectification and negative differential resistance behavior}, author = {Cui, Bin and Xu, Yuqing and Ji, Guomin and Wang, Hui and Zhao, Wenkai and Zhai, Yaxin and Li, Dongmei and Liu, Desheng}, journal = {Organic Electronics}, volume = {15}, number = {2}, pages = {484--490}, year = {2014}, keywords = {area:molecular electronics,doping,experimental comparison,gate modulation,non-equilibrium Green's function,rectification,unimolecular diode}, area = {molecular electronics} doi = {10.1016/j.orgel.2013.11.039}, }  W.H. Khoo & S.M. Sultan, A study on the gas sensing effect on current-voltage characteristics of ZnO nanostructures, pp. 221--224 (2014) Adsorption,CO,Current-voltage characteristics,DFT,DFT technique,Electrodes,Green's function methods,I-V characteristics,II-VI semiconductors,NH3,NO2,Nanowires,Quantum Wise,Scattering,Zinc oxide,ZnO,ZnOammonia,area:2dmat,bias voltage,carbon compounds,current-voltage characteristics,density functional theory,gas molecule,gas sensing effect,gas sensors,nanosensors,nanostructure,nanostructured materials,nitrogen compounds,nonequilibrium Green's function,sensitivity factor,zinc compounds 2dmat Abstract: Current-voltage characteristics of ZnO nanostructures were studied under different gas ambient using nonequilibrium Green's function and density functional theory, DFT technique. It was found that I-V characteristics of ZnO nanostructures depend strongly on the type of gas molecules present. The sensitivity factor of more than 200% achieved with the presence of a single molecule of NO2 gas. Meanwhile, there were no significant changes towards CO and NH3 gas molecules. However, CO adsorption can significantly suppress the transmission spectrum of ZnO nanostructures. Under the same applied bias voltage, the current through ZnO nanostructures decreases with increasing CO concentrations. BibTeX: @inproceedings{Khoo2014, title = {A study on the gas sensing effect on current-voltage characteristics of ZnO nanostructures}, author = {Khoo, W H and Sultan, S M}, booktitle = {2014 IEEE International Conference on Semiconductor Electronics}, pages = {221--224}, year = {2014}, keywords = {Adsorption,CO,Current-voltage characteristics,DFT,DFT technique,Electrodes,Green's function methods,I-V characteristics,II-VI semiconductors,NH3,NO2,Nanowires,Quantum Wise,Scattering,Zinc oxide,ZnO,ZnOammonia,area:2dmat,bias voltage,carbon compounds,current-voltage characteristics,density functional theory,gas molecule,gas sensing effect,gas sensors,nanosensors,nanostructure,nanostructured materials,nitrogen compounds,nonequilibrium Green's function,sensitivity factor,zinc compounds}, area = {2dmat} doi = {10.1109/SMELEC.2014.6920836}, }  M.A. Mehrabova, H.S. Orujov & N.H. Hasanov, Ab initio study of defects in CdMnTe: Electronic structure and related properties, International Journal of Materials Science and Applications, Vol. 3(6-1), pp. 24--32 (2014) Ab Initio,Defect,Density of States,Electron Structure,Frenkel Pair,Interstitial Atom,Magnetic Moment,Semimagnetic Semiconductor,Vacancy,area:materials materials Abstract: Band structure, density of states, total energy and magnetic moment are calculated for ideal and defective supercell CdTe and CdMnTe by ab initio method. The optimization of crystal structure and atom relaxation has been carried out. The band gap, local levels in the band gap and magnetic moments are defined for various defective supercell CdTe and CdMnTe in ferromagnetic and antiferromagnetic states. It has been defined that as Mn atoms, the vacancy, interstitial atom and Frenkel pair in the crystal structure form magnetic moment. BibTeX: @article{Mehrabova2014a, title = {Ab initio study of defects in CdMnTe: Electronic structure and related properties}, author = {Mehrabova, M A and Orujov, H S and Hasanov, N H}, journal = {International Journal of Materials Science and Applications}, volume = {3}, number = {6-1}, pages = {24--32}, year = {2014}, keywords = {Ab Initio,Defect,Density of States,Electron Structure,Frenkel Pair,Interstitial Atom,Magnetic Moment,Semimagnetic Semiconductor,Vacancy,area:materials}, area = {materials} doi = {10.11648/j.ijmsa.s.2014030601.16}, }  W.-F. Sun, X. Wang & Z. Sun, Ab initio study of electronic structure, quantum transport and optical absorption properties of polyacene quinone radical polymers, IEEE Transactions on Dielectrics and Electrical Insulation, Vol. 21(4), pp. 1801--1808 (2014) Ab initio,Atom optics,Electrodes,Optical polarization,Optical polymers,Plastics,Quantum mechanics,area:molecular electronics,electronic structure,polyacene quinone radical polymer,quantum transport molecular electronics Abstract: Semiempirical quantum mechanical calculations have been implemented to study the molecular structure, electronic structure, optical properties of polyacene quinone radical polymers, and the quantum transport properties are also been calculated through combination of the numerical atomic orbitals basis set method based on density functional theory with the non-equilibrium Green's function formalism. The polyacene quinone radical polymers exhibit similar elastic modulus to the carbon nanotubes. The electronic molecular orbitals and energy bands of polyacene quinone radical polymers show insulator features, with the great conjugated bonds formed in polymer molecules resulting in extreme high polarization and dielectric constants, and the Fermi energy and band-gaps of ultraviolet range are static with the variation of polymerization degree. The aluminum electrodes with crystallographic (001) surfaces have been used in the electronic transport calculations, which indicate the quantum conductance spectrum changes with the varied strain and polymerization degree, however appears no explicit change, representing large open-gap feature of insulators. Ultraviolet-visible absorption spectra show a few characteristic peaks, the positions and number of which varying with polymerization degree, predicting that polyacene quinone radical polymers, as high dielectric functional materials, could be applied to ultraviolet optoelectronic nanoscale quantum devices. BibTeX: @article{Sun2014, title = {Ab initio study of electronic structure, quantum transport and optical absorption properties of polyacene quinone radical polymers}, author = {Sun, W.-F. and Wang, X and Sun, Z}, journal = {IEEE Transactions on Dielectrics and Electrical Insulation}, volume = {21}, number = {4}, pages = {1801--1808}, year = {2014}, keywords = {Ab initio,Atom optics,Electrodes,Optical polarization,Optical polymers,Plastics,Quantum mechanics,area:molecular electronics,electronic structure,polyacene quinone radical polymer,quantum transport}, area = {molecular electronics} doi = {10.1109/TDEI.2014.004331}, }  Pankaj Srivastava, Subhra Dhar & Neeraj K. Jaiswal, Ab initio study of gold-doped zigzag graphene nanoribbons, Applied Physics A, Vol. 117(4), pp. 1997--2008 (2014) area:graphene,electron transport,gold,graphene,nanoribbon graphene Abstract: The electronic transport properties of zigzag graphene nanoribbons (ZGNRs) through covalent functionalization of gold (Au) atoms is investigated by using non-equilibrium Green's function combined with density functional theory. It is revealed that the electronic properties of Au-doped ZGNRs vary significantly due to spin and its non-inclusion. We find that the DOS profiles of Au-adsorbed ZGNR due to spin reveal very less number of states available for conduction, whereas non-inclusion of spin results in higher DOS across the Fermi level. Edge Au-doped ribbons exhibit stable structure and are energetically more favorable than the center Au-doped ZGNRs. Though the chemical interaction at the ZGNR-Au interface modifies the Fermi level, Au-adsorbed ZGNR reveals semimetallic properties. A prominent qualitative change of the I-V curve from linear to nonlinear is observed as the Au atom shifts from center toward the edges of the ribbon. Number of peaks present near the Fermi level ensures conductance channels available for charge transport in case of Au-center-substituted ZGNR. We predict semimetallic nature of the Au-adsorbed ZGNR with a high DOS peak distributed over a narrow energy region at the Fermi level and fewer conductance channels. Our calculations for the magnetic properties predict that Au functionalization leads to semiconducting nature with different band gaps for spin up and spin down. The outcomes are compared with the experimental and theoretical results available for other materials. BibTeX: @article{Srivastava2014d, title = {Ab initio study of gold-doped zigzag graphene nanoribbons}, author = {Srivastava, Pankaj and Dhar, Subhra and Jaiswal, Neeraj K}, journal = {Applied Physics A}, publisher = {Springer Berlin Heidelberg}, volume = {117}, number = {4}, pages = {1997--2008}, year = {2014}, keywords = {area:graphene,electron transport,gold,graphene,nanoribbon}, area = {graphene} doi = {10.1007/s00339-014-8608-8}, }  Ankit Kumar Verma, Bahniman Ghosh, Bhaskar Awadhiya & Tangudu Bharat Kumar, Ab-Initio Modeling of Effect of Boron and Phosphorus Doping in CoFe/MgO Magnetic Tunnel Junctions, Journal of Low Power Electronics, Vol. 10(3), pp. 361--364(4) (2014) area:interfaces,area:nvm,magnetic random access memory (MRAM),magnetic tunnel junction (MTJ),spin dependent generalized gradient approximation,spintronics,tunneling magneto-resistance (TMR) interfaces,nvm Abstract: In this work analysis of Boron and Phosphorus doping in CoFe/MgO Magnetic Tunnel Junction has been carried out using first principle calculations. Boron and Phosphorus are doped in CoFe electrode, at electrode barrier interface and in the bulk. In case of Boron doping tunneling magneto-resistance (TMR) of magnetic tunnel junction is reduced to a much lower value when it is doped at electrode barrier interface instead of bulk. However in case of Phosphorus doping TMR is almost same as when Boron atoms are doped in the bulk of electrode. Boron atoms present at interface cause distortion in δ1 state symmetry which in turn tempers majority channel conductance. So prevention of Boron doping at interface or doping of Phosphorus atoms could result in the device having much higher value of TMR. BibTeX: @article{Verma2014, title = {Ab-Initio Modeling of Effect of Boron and Phosphorus Doping in CoFe/MgO Magnetic Tunnel Junctions}, author = {Verma, Ankit Kumar and Ghosh, Bahniman and Awadhiya, Bhaskar and Kumar, Tangudu Bharat}, journal = {Journal of Low Power Electronics}, volume = {10}, number = {3}, pages = {361--364(4)}, year = {2014}, keywords = {area:interfaces,area:nvm,magnetic random access memory (MRAM),magnetic tunnel junction (MTJ),spin dependent generalized gradient approximation,spintronics,tunneling magneto-resistance (TMR)}, area = {interfaces,nvm} doi = {10.1166/jolpe.2014.1349}, }  Anurag Srivastava, Sumit Kumar Jain & Purnima Swarup Khare, Ab-initio study of structural, electronic, and transport properties of zigzag GaP nanotubes, Journal of Molecular Modeling, Vol. 20(3), pp. 2171 (2014) Ab-initio,Band structure,Buckling,GaP,I-V curve,Nanotubes,area:nanotubes nanotubes Abstract: Stability and electronic properties of zigzag (3textlessntextless6) gallium phosphide nanotubes (GaP NTs) have been analyzed by employing a systematic ab-intio approach based on density functional theory using generalized gradient approximation with revised Perdew Burke Ernzerhoff type parameterization. Diameter dependence of bond length, buckling, binding energy, and band gap has been investigated and the analysis shows that the bond length and buckling decreases with increasing diameter of the tube, highest binding energy of (16, 0) confirms this as the most stable amongst all the NTs taken into consideration. The present GaP NTs shows direct band gap and it increases with diameter of the tubes. Using a two probe model for (4, 0) NT the I-V relationship shows an exponential increase in current on applying bias voltage beyond 1.73 volt. BibTeX: @article{Srivastava2014a, title = {Ab-initio study of structural, electronic, and transport properties of zigzag GaP nanotubes}, author = {Srivastava, Anurag and Jain, Sumit Kumar and Khare, Purnima Swarup}, journal = {Journal of Molecular Modeling}, publisher = {Springer Berlin Heidelberg}, volume = {20}, number = {3}, pa