Splitting of the Raman $2D$ band of graphene subjected to strain

TL;DR

This paper extends the double-resonance Raman model to explain how uniaxial strain affects the splitting of the graphene 2D band, revealing insights into its origin and dependence on strain and polarization.

Contribution

It introduces an expanded Raman model that accounts for strain direction and polarization effects on the 2D band splitting in graphene.

Findings

The model accurately predicts strain and polarization dependence of the 2D band splitting.

The analysis provides new understanding of the 2D band's origin in strained graphene.

Predictions align well with recent experimental results.

Abstract

The Raman $2D$-band -important for the analysis of graphene- shows a splitting for uniaxial strain. The splitting depends on the strength and direction of the applied strain and on the polarization of the incident and outgoing light. We expand the double-resonance Raman model in order to explain the strain direction dependence and the polarization dependence of the splitting. The analysis of this splitting gives new insight into the origin of the $2D$-band. Our prediction of the strain direction and polarization dependence agrees well with recent experiments.