Two-dimensional graphene with structural defects: elastic mean free path, minimum conductivity, and Anderson transition.
نویسندگان
چکیده
Quantum transport properties of disordered graphene with structural defects (Stone-Wales and divacancies) are investigated using a realistic π-π* tight-binding model elaborated from ab initio calculations. Mean free paths and semiclassical conductivities are then computed as a function of the nature and density of defects (using an order-N real-space Kubo-Greenwood method). By increasing the defect density, the decay of the semiclassical conductivities is predicted to saturate to a minimum value of 4e2/πh over a large range (plateau) of carrier density (>0.5×10(14) cm(-20). Additionally, strong contributions of quantum interferences suggest that the Anderson localization regime could be experimentally measurable for a defect density as low as 1%.
منابع مشابه
Effect of structural defects on the thermal conductivity of graphene: From point to line defects to haeckelites
We use nonequilibrium molecular-dynamics simulations to study the effect of structural defects on the thermal conductivity λ of graphene. Focusing on 5-7 and 5-8 defects in the graphene honeycomb lattice, we find that λ depends sensitively on whether the defects are isolated, form lines, or form extended arrangements in haeckelites. Our results indicate that the presence of defects makes λ anis...
متن کاملBallistic Thermal Transport in Carbyne and Cumulene with Micron-Scale Spectral Acoustic Phonon Mean Free Path
The elastic modulus of carbyne, a one-dimensional carbon chain, was recently predicted to be much higher than graphene. Inspired by this discovery and the fundamental correlation between elastic modulus and thermal conductivity, we investigate the intrinsic thermal transport in two carbon allotropes: carbyne and cumulene. Using molecular dynamics simulations, we discover that thermal conductivi...
متن کاملComputational study of the thermal conductivity in defective carbon nanostructures
We use nonequilibrium molecular dynamics simulations to study the adverse role of defects including isotopic impurities on the thermal conductivity of carbon nanotubes, graphene, and graphene nanoribbons. We find that even in structurally perfect nanotubes and graphene, isotopic impurities reduce thermal conductivity by up to one half by decreasing the phonon mean-free path. An even larger ther...
متن کاملMono-Mono-Mono and Bi-Bi-Bi three-layer graphene systems’ optical conductivity
Investigating the longitudinal optical conductivity of graphene systems, which is the mostimportant property for opto-electronic devices, for three-layer graphene systems theoretically and numerically is the main purpose of this study. Each layer can be mono- or bi-layer graphene. Separation between layers has been denoted by d, selected to be about ten nanometers. The carrier densities i...
متن کاملEffect of Stone-Wales defects on the thermal conductivity of graphene.
The problem of phonon scattering by strain fields caused by Stone-Wales (SW) defects in graphene is studied in the framework of the deformation potential approach. An explicit form of the phonon mean free path due to phonon-SW scattering is obtained within the Born approximation. The mean free path demonstrates a specific q-dependence varying as q (-3) at low wavevectors and taking a constant v...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Physical review letters
دوره 106 4 شماره
صفحات -
تاریخ انتشار 2011