Distortion of the perfect lattice structure in bilayer graphene

TL;DR

This paper investigates the tendency of bilayer graphene to adopt distorted lattice structures, showing that the ground state favors a finite distortion influenced by carrier density and interlayer potential differences.

Contribution

It introduces a model for bilayer graphene distortion and analyzes how external parameters affect the equilibrium configuration, revealing a preference for distorted ground states.

Findings

Finite distortion is energetically favored in bilayer graphene.

External parameters like carrier density influence the distortion magnitude.

The model predicts how potential differences modify the equilibrium structure.

Abstract

We consider the instability of bilayer graphene with respect to a distorted configuration in the same spirit as the model introduced by Su, Schrieffer and Heeger. By computing the total energy of a distorted bilayer, we conclude that the ground state of the system favors a finite distortion. We explore how the equilibrium configuration changes with carrier density and an applied potential difference between the two layers.