Edge effect on resistance scaling rules in graphene nanostructures

TL;DR

This study investigates how edges influence electrical resistance scaling in graphene nanostructures, revealing that edge effects cause strong localization in nanoribbons, which can be mitigated by structural modifications.

Contribution

The paper provides experimental evidence of edge effects on resistance scaling in graphene nanostructures and explores how these effects change with geometry and layering.

Findings

Edge effects induce strong localization in graphene nanoribbons.

Widening the structure reduces edge influence on transport.

Adding layers diminishes the edge effect.

Abstract

We report an experimental investigation of the edge effect on the room-temperature transport in graphene nanoribbon and graphene sheet (both single-layer and bilayer). By measuring the resistance scaling behaviors at both low and high carrier densities, we show that the transport of single-layer nanoribbons lies in a strong localization regime, which can be attributed to an edge effect. We find that this edge effect can be weakened by enlarging the width, decreasing the carrier densities or adding an extra layer. From graphene nanoribbon to graphene sheet, the data show a dimensional crossover of the transport regimes possibly due to the drastic change of the edge effect.