Phonon spectroscopy through the electronic density of states in graphene

TL;DR

This paper investigates how phonon features appear in the electronic density of states of graphene, developing a method to extract electron-phonon coupling strength and analyzing how these features evolve with doping.

Contribution

A novel procedure is introduced for extracting the electron-phonon renormalization parameter from graphene's density of states, revealing doping-dependent phonon structures.

Findings

Phonon structures are identifiable in the density of states.

The electron-phonon coupling parameter $mbda$ increases with doping.

Phonon features lose particle-hole symmetry at higher doping levels.

Abstract

We study how phonon structure manifests itself in the electronic density of states of graphene. A procedure for extracting the value of the electron-phonon renormalization $\lambda$ is developed. In addition, we identify direct phonon structures. With increasing doping, these structures, along with $\lambda$, grow in amplitude and no longer display particle-hole symmetry.