Phonon and structural changes in deformed Bernal stacked bilayer graphene

TL;DR

This study uses Raman spectroscopy to investigate how uniaxial tension affects Bernal bilayer graphene, revealing structural and phonon changes that could impact band-gap engineering.

Contribution

First Raman spectroscopic analysis of Bernal bilayer graphene under uniaxial tension highlighting inhomogeneous stress effects and symmetry removal.

Findings

Inhomogeneous stress affects phonon modes.

Removal of inversion symmetry observed.

Potential implications for band-gap engineering.

Abstract

We present the first Raman spectroscopic study of Bernal bilayer graphene flakes under uniaxial tension. Apart from a purely mechanical behavior in flake regions where both layers are strained evenly, certain effects stem from inhomogeneous stress distribution across the layers. These phenomena such as the removal of inversion symmetry in bilayer graphene may have important implications in the band-gap engineering providing an alternative route to induce the formation of a band-gap.