Massive Dirac Fermions Signal in Raman Spectrum of Graphene

TL;DR

This paper demonstrates how Raman spectroscopy can be used to measure the mass of Dirac fermions in graphene caused by sublattice symmetry breaking, linking pseudospin polarization to observable spectral features.

Contribution

It introduces a novel method to determine the mass of massive Dirac fermions in graphene via Raman spectroscopy, based on the pseudospin polarization mechanism.

Findings

Raman spectra reveal signatures of massive Dirac fermions in graphene.

The method provides a conventional way to measure sublattice-induced mass.

Pseudospin polarization explains the Raman spectral features.

Abstract

Massless Dirac fermions in graphene can acquire a mass through different kinds of sublattice-symmetry-breaking perturbations, and there is a growing need to determine this mass using a conventional method. We describe how the mass caused by a staggered sublattice potential is determined using Raman spectroscopy and explain the mechanism in terms of the pseudospin polarization of massive Dirac fermions.