Edge-state transport in gapped bilayer graphene

TL;DR

This paper studies electronic edge-state conduction in gapped bilayer graphene, revealing how edge terminations influence non-topological edge states and their potential for non-local resistance effects.

Contribution

It demonstrates the existence and tunability of edge states in gapped bilayer graphene depending on edge termination, supported by band structure calculations.

Findings

Edge states cause non-local resistance in gBLG.

Edge localization can be switched by electron energy.

Edge states depend on termination, not topological properties.

Abstract

We investigate electronic transport in gapped bilayer graphene (gBLG) devices. For certain edge terminations -typically a combination of zigzag, armchair, and bearded types - we observe edge state conduction within the band gap, which is opened by a potential bias between the two layers. The edge states can generate a non-local resistance, in line with recent experiments [1]. Band structure calculations of gBLG nanoribbons corroborate the existence of the edge states, whose edge localization can be switched by tuning the electron energy. Their existence strongly depends on the edge termination and does not originate from a topological bulk-boundary correspondence.