Electronic transport in graphene-based structures: an effective cross section approach

TL;DR

This paper introduces an effective cross section approach to model electronic transport in graphene-based nanostructures, enabling accurate conductance estimation with reduced computational effort using large-scale simulations and first-principles data.

Contribution

It presents a novel method combining scaling theory and effective cross sections to efficiently predict conductance in low-dimensional carbon structures from first principles.

Findings

Effective cross sections accurately estimate conductance in different regimes.

Method reduces computational cost for large mesoscopic systems.

Simulation results validate the approach across various defect configurations.

Abstract

We show that transport in low-dimensional carbon structures with finite concentrations of scatterers can be modeled by utilising scaling theory and effective cross sections. Our reults are based on large scale numerical simulations of carbon nanotubes and graphene nanoribbons, using a tightbinding model with parameters obtained from first principles electronic structure calculations. As shown by a comprehensive statistical analysis, the scattering cross sections can be used to estimate the conductance of a quasi-1D system both in the Ohmic and localized regimes. They can be computed with good accuracy from the transmission functions of single defects, greatly reducing the computational cost and paving the way towards using first principles methods to evaluate the conductance of mesoscopic systems, consisting of millions of atoms.