Energy Band Gap Engineering of Graphene Nanoribbons

TL;DR

This paper demonstrates how lithographic patterning can be used to engineer and control the energy band gap in graphene nanoribbons by varying their width and orientation, impacting electronic transport properties.

Contribution

It provides experimental evidence that the energy gap in graphene nanoribbons scales inversely with their width, enabling band gap engineering through lithography.

Findings

Energy gaps increase as ribbon width decreases.

Energy gap scales inversely with ribbon width.

Conductance measurements confirm band gap tunability.

Abstract

We investigate electronic transport in lithographically patterned graphene ribbon structures where the lateral confinement of charge carriers creates an energy gap near the charge neutrality point. Individual graphene layers are contacted with metal electrodes and patterned into ribbons of varying widths and different crystallographic orientations. The temperature dependent conductance measurements show larger energy gaps opening for narrower ribbons. The sizes of these energy gaps are investigated by measuring the conductance in the non-linear response regime at low temperatures. We find that the energy gap scales inversely with the ribbon width, thus demonstrating the ability to engineer the band gap of graphene nanostructures by lithographic processes.