Charge Transport in Disordered Graphene-Based Low Dimensional Materials

TL;DR

This review discusses the electronic transport properties of disordered low-dimensional carbon materials like graphene nanoribbons, highlighting how disorder and symmetry influence conduction, localization, and edge effects.

Contribution

It provides analytical expressions for mean free paths and explores the impact of disorder and edge roughness on transport regimes in graphene-based nanostructures.

Findings

Transport properties are highly sensitive to disorder and symmetry.

Analytical formulas for elastic mean free path are derived.

Edge disorder significantly affects conduction in nanoribbons.

Abstract

Two-dimensional graphene, carbon nanotubes and graphene nanoribbons represent a novel class of low dimensional materials that could serve as building blocks for future carbon-based nanoelectronics. Although these systems share a similar underlying electronic structure, whose exact details depend on confinement effects, crucial differences emerge when disorder comes into play. In this short review, we consider the transport properties of these materials, with particular emphasis to the case of graphene nanoribbons. After summarizing the electronic and transport properties of defect-free systems, we focus on the effects of a model disorder potential (Anderson-type), and illustrate how transport properties are sensitive to the underlying symmetry. We provide analytical expressions for the elastic mean free path of carbon nanotubes and graphene nanoribbons, and discuss the onset of weak and strong localization regimes, which are genuinely dependent on the transport dimensionality. We also consider the effects of edge disorder and roughness for graphene nanoribbons in relation to their armchair or zigzag orientation.