Electron-Phonon Interactions in Graphene, Bilayer Graphene, and Graphite

TL;DR

This study uses first-principles calculations to compare electron-phonon interactions and Fermi velocity renormalization in doped graphene, bilayer graphene, and graphite, revealing significant differences influenced by interlayer interactions.

Contribution

It provides a detailed first-principles analysis of electron-phonon effects across graphene-based materials, highlighting the impact of interlayer coupling.

Findings

Fermi velocity renormalization is ~30% larger in bilayer graphene and graphite than in graphene.

Interlayer interactions significantly influence electron-phonon coupling effects.

Results align with recent photoemission and Raman spectroscopy experiments.

Abstract

Using first-principles techniques, we calculate the renormalization of the electron Fermi velocity and the vibrational lifetimes arising from electron-phonon interactions in doped bilayer graphene and in graphite and compare the results with the corresponding quantities in graphene. For similar levels of doping, the Fermi velocity renormalization in bilayer graphene and in graphite is found to be approximately 30% larger than that in graphene. In the case of bilayer graphene, this difference is shown to arise from the interlayer interaction. We discuss our findings in the light of recent photoemission and Raman spectroscopy experiments.