Control of Raman scattering quantum interference pathways in graphene

TL;DR

This study demonstrates how tuning laser excitation energy and doping levels in graphene can control quantum interference pathways in Raman scattering, revealing insights into electronic excitation lifetimes and interference effects.

Contribution

It introduces a method to control Raman scattering pathways in graphene by tuning excitation energy and doping, providing new insights into quantum interference mechanisms.

Findings

Raman excitation profile of G mode depends linearly on doping

Doping enhances electron-electron interactions affecting Raman pathways

Quantum interference in Raman scattering can be engineered in doped graphene

Abstract

Graphene is an ideal platform to study the coherence of quantum interference pathways by tuning doping or laser excitation energy. The latter produces a Raman excitation profile that provides direct insight into the lifetimes of intermediate electronic excitations and, therefore, on quantum interference, which has so far remained elusive. Here, we control the Raman scattering pathways by tuning the laser excitation energy in graphene doped up to 1.05eV, above what achievable with electrostatic doping. The Raman excitation profile of the G mode indicates its position and full width at half maximum are linearly dependent on doping. Doping-enhanced electron-electron interactions dominate the lifetime of Raman scattering pathways, and reduce Raman interference. This paves the way for engineering quantum pathways in doped graphene, nanotubes and topological insulators.