Electron-phonon coupling-induced kinks in the sigma band of graphene
Abstract
Angle-resolved photoemission spectroscopy reveals pronounced kinks in the dispersion of the sigma band of graphene. Such kinks are usually caused by the combination of a strong electron-boson interaction and the cut-off in the Fermi-Dirac distribution. They are therefore not expected for the band of graphene that has a binding energy of more than 3.5 eV. We argue that the observed kinks are indeed caused by the electron-phonon interaction, but the role of the Fermi-Dirac distribution cutoff is assumed by a cut-off in the density of states. The existence of the effect suggests a very weak coupling of holes in the band not only to the electrons of graphene but also to the substrate electronic states. This is confirmed by the presence of such kinks for graphene on several different substrates that all show a strong coupling constant of lambda=1.
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Cite
@article{arxiv.1305.6210,
title = {Electron-phonon coupling-induced kinks in the sigma band of graphene},
author = {Federico Mazzola and Justin W. Wells and Rositza Yakimova and Soren Ulstrup and Jill A. Miwa and Richard Balog and Marco Bianchi and Mats Leandersson and Johan Adell and Philip Hofmann and T. Balasubramanian},
journal= {arXiv preprint arXiv:1305.6210},
year = {2013}
}