Signatures of disorder in the minimum conductivity of graphene

TL;DR

This paper investigates how edge and bulk disorder affect the minimum conductivity in graphene ribbons, revealing a non-monotonic size scaling behavior crucial for designing better graphene-based nanoelectronics.

Contribution

It provides the first combined experimental and theoretical analysis linking disorder types to conductivity scaling in graphene, offering new insights into quantum transport mechanisms.

Findings

Discovered a non-monotonic size dependence of minimum conductivity.

Attributed conductivity features to edge and bulk disorder levels.

Provided guidelines for optimizing graphene device performance.

Abstract

Graphene has been proposed as a promising material for future nanoelectronics because of its unique electronic properties. Understanding the scaling behavior of this new nanomaterial under common experimental conditions is of critical importance for developing graphene-based nanoscale devices. We present a comprehensive experimental and theoretical study on the influence of edge disorder and bulk disorder on the minimum conductivity of graphene ribbons. For the first time, we discovered a strong non-monotonic size scaling behavior featuring a peak and saturation minimum conductivity. Through extensive numerical simulations and analysis, we are able to attribute these features to the amount of edge and bulk disorder in graphene devices. This study elucidates the quantum transport mechanisms in realistic experimental graphene systems, which can be used as a guideline for designing graphene-based nanoscale devices with improved performance.