Graphene nanoribbons with wings

TL;DR

This study explores how adding wing-like extensions to graphene nanoribbons alters electronic transport, revealing significant contributions from distant localized states and demonstrating the effectiveness of tight-binding simulations.

Contribution

It introduces a novel device geometry with wings and shows how this modifies Coulomb blockade behavior and transport properties, supported by experimental and simulation data.

Findings

Wings significantly modify Coulomb-blockade transport.

Localized states far from the center contribute to conduction.

Tight-binding simulations match experimental results qualitatively and quantitatively.

Abstract

We have investigated electronic transport in graphene nanoribbon devices with additional bar-shaped extensions ("wings") at each side of the device. We find that the Coulomb-blockade dominated transport found in conventional ribbons is strongly modified by the presence of the extensions. States localized far away from the central ribbon contribute significantly to transport. We discuss these findings within the picture of multiple coupled quantum dots. Finally, we compare the experimental results with tight-binding simulations which reproduce the experiment both qualitatively and quantitatively.