Coulomb blockade in graphene nanoribbons

TL;DR

This paper explains the energy gap observed in graphene nanoribbons through Coulomb blockade, emphasizing the role of electron interactions at quantum dots formed by edge roughness, aligning well with experimental data.

Contribution

It introduces a Coulomb blockade-based model to interpret transport experiments in graphene nanoribbons, highlighting the significance of edge-induced quantum dots.

Findings

Good agreement with experimental data using a single fitting parameter

Electron interactions are crucial at edge-formed quantum dots

Energy gap can be explained by Coulomb blockade effects

Abstract

We propose that recent transport experiments revealing the existence of an energy gap in graphene nanoribbons may be understood in terms of Coulomb blockade. Electron interactions play a decisive role at the quantum dots which form due to the presence of necks arising from the roughness of the graphene edge. With the average transmission as the only fitting parameter, our theory shows good agreement with the experimental data.