Effect of inelastic collisions on multiphonon Raman scattering in graphene

TL;DR

This paper calculates two- and four-phonon Raman scattering probabilities in graphene, demonstrating how overtone peak intensities reveal the relative rates of inelastic electron processes like electron-phonon and electron-electron interactions.

Contribution

It provides a theoretical framework linking Raman spectral features to inelastic electron scattering rates in graphene.

Findings

Overtone peak intensities encode electron scattering rates.

Electron-electron scattering rate can be deduced from Raman spectra.

Theoretical calculations match experimental observations.

Abstract

We calculate the probabilities of two- and four-phonon Raman scattering in graphene and show how the relative intensities of the overtone peaks encode information about relative rates of different inelastic processes electrons are subject to. If the most important processes are electron-phonon and electron-electron scattering, the rate of the latter can be deduced from the Raman spectra.