Coherent transport through graphene nanoribbons in the presence of edge disorder

TL;DR

This paper investigates electron transport in graphene nanoribbons with rough edges, revealing how edge disorder affects localization and symmetry, using a scalable numerical method to analyze long ribbons.

Contribution

It introduces a modular recursive Green's function technique for efficient simulation of large graphene nanoribbons with edge disorder.

Findings

Edge disorder causes Anderson localization in long ribbons.

Broken sublattice symmetry influences scattering states.

Localization length spans over 10 orders of magnitude.

Abstract

We simulate electron transport through graphene nanoribbons of experimentally realizable size (length L up to 2 micrometer, width W approximately 40 nm) in the presence of scattering at rough edges. Our numerical approach is based on a modular recursive Green's function technique that features sub-linear scaling with L of the computational effort. We identify the influence of the broken A-B sublattice (or chiral) symmetry and of K-K' scattering by Fourier spectroscopy of individual scattering states. For long ribbons we find Anderson-localized scattering states with a well-defined exponential decay over 10 orders of magnitude in amplitude.