Photoemission studies of graphene have resulted in a long-standing controversy concerning the strength of the experimental electron-phonon interaction in comparison with theoretical calculations. Using high-resolution angle-resolved photoemission spectroscopy we study graphene grown on a copper substrate, where the metallic screening of the substrate substantially reduces the electron-electron interaction, simplifying the comparison of the electron-phonon interaction between theory and experiment. By taking the nonlinear bare bandstructure into account, we are able to show that the strength of the electron-phonon interaction does indeed agree with theoretical calculations. In addition, we observe a significant bandgap at the Dirac point of graphene.
@article{arxiv.1108.2566,
title = {Electron-Phonon Coupling in Highly-Screened Graphene},
author = {David A. Siegel and Choongyu Hwang and Alexi V. Fedorov and Alessandra Lanzara},
journal= {arXiv preprint arXiv:1108.2566},
year = {2015}
}