Uniaxial strain on gapped graphene

TL;DR

This paper investigates how uniaxial strain affects the electronic band structure of two types of gapped graphene, revealing different behaviors in band gap location and size through analytical and numerical methods.

Contribution

It provides a comparative analysis of strain effects on staggered and Kekulé gapped graphene models using both tight-binding and Dirac fermion approaches.

Findings

Strain shifts the band gap location in staggered model.

In Kekulé model, strain reduces the band gap and shifts contact points after closure.

Analytical and numerical methods confirm the strain-induced band structure changes.

Abstract

We study the effect of uniaxial strain on the electronic band structure of gapped graphene. We consider two types of gapped graphene, one which breaks the symmetry between the two triangular sublattices (staggered model), and another which alternates the bonds on the honeycomb lattice (Kekul\'e model). In the staggered model, the effect of strains below a critical value is only a shift of the band gap location. In the Kekul\'e model, as strain is increased, band gap location is initially pinned to a corner of the Brillouin zone while its width diminishes, and after gap closure the location of the contact point begins to shift. Analytic and numerical results are obtained for both the tight-binding and Dirac fermion descriptions of gapped graphene.