The fundamental question of how chirality affects the electronic coupling of a nanotube to metal contacts is important for tile application of nanotubes as nanowires. We show that metallic-zigzag nanotubes are superior to armchair nanotubes as nanowires, by modeling the metal-nanotube interfacc. More specifically, we show that as a function of coupling strength, the total electron transmission ...

We study the electronic correlation effects in armchair graphene nanoribbons that have been recently proposed to be the building blocks of spin qubits. The armchair edges give rise to peculiar quantum interferences and lead to quenched kinetic energy of the itinerant carriers at appropriate doping level. This is a beautiful one-dimensional analogy of the Landaulevel formation in two dimensions ...

Using ab initio calculation coupled with the bond-order-length-strength (BOLS) approximation, we investigate the configurations and electronic properties of (α, β)-graphyne nanoribbons (GYNRs) with armchair (AGYNRs) and zigzag (ZGYNRs) edges. Our investigation shows that the armchair-edged β-GYNRs and all α-GYNRs are semiconductors with suitable band-gaps, and that their band-gaps increase as t...

Density functional theory (DFT) calculations were performed to compute nitrogen-14 and boron-11 nuclear quadrupole resonance (NQR) spectroscopy parameters in the representative model of armchair boron nitride nanotube (BNNT) for the first time. The considered model consisting of 1 nm length of H-capped (5, 5) single-wall BNNT were first allowed to fully relax and then the NQR calculations were ...

Gradient-corrected density functional theory (DFT) computations were performed to investigate the geometry, electronic property, formation energy, and reactivity of Stone-Wales (SW) defects in zigzag-edge and armchair-edge boron nitride nanoribbons (BNNRs). The formation energies of SW defects increase with an increase in the widths of BNNRs and are orientation-dependent. SW defects considerabl...

Density functional theory (DFT) calculations were performed to compute nitrogen-14 and boron-11 nuclear quadrupole resonance (NQR) spectroscopy parameters in the representative model of armchair boron nitride nanotube (BNNT) for the first time. The considered model consisting of 1 nm length of H-capped (5, 5) single-wall BNNT were first allowed to fully relax and then the NQR calculations were ...

We theoretically study the magnetoresistance of single wall carbon nanotubes (SWCNTs) in the ballistic transport regime, using a standard tight-binding approach. The main attention is directed to spin-polarized electrical transport in the presence of either axial or perpendicular magnetic field. The method takes into account both Zeeman splitting as well as size and chirality effects. These fac...

This paper discusses several important issues in a molecular dynamics simulation for analysing carbon nanotubes and their mechanical properties. In particular, the paper addresses the problems in selecting appropriate inter-atomic potentials, number of thermostat atoms, thermostat techniques, time and displacement steps and number of relaxation steps to reach the dynamic equilibrium. Based on t...

The creation of magnetic storage devices by decoration of a graphene sheet by magnetic transition-metal adatoms, utilizing the high in-plane versus out-of-plane magnetic anisotropy energy (MAE), has recently been proposed. This concept is extended in our density-functional-based modeling study by incorporating the influence of the graphene edge on the MAE. We consider triangular graphene flakes...

Spin polarized density functional theory has been used to investigate the structural stability and electronic properties of extrinsic and intrinsic defects in boron nitride nanotubes. Carbon substitutional defects under nitrogen rich and boron-rich growth conditions have the lowest heats of formation compared to boron and nitrogen antisites. Creating a defect reduces the band gap of the nanotub...