We obtained the spectral function of the graphite H point using high resolution angle resolved photoelectron spectroscopy (ARPES). The extracted width of the spectral function (inverse of the photo-hole lifetime) near the H point is approximately proportional to the energy as expected from the linearly increasing density of states (DOS) near the Fermi energy. This is well accounted by our electron-phonon coupling theory considering the peculiar electronic DOS near the Fermi level. And we also investigated the temperature dependence of the peak widths both experimentally and theoretically. The upper bound for the electron-phonon coupling parameter is ~0.23, nearly the same value as previously reported at the K point. Our analysis of temperature dependent ARPES data at K shows that the energy of phonon mode of graphite has much higher energy scale than 125K which is dominant in electron-phonon coupling.
@article{arxiv.0903.0681,
title = {High resolution angle resolved photoemission studies on quasi-particle dynamics in graphite},
author = {C. S. Leem and B. J. Kim and Chul Kim and S. R. Park and Min-Kook Kim and S. Johnston and T. Ohta and A. Bostwick and Hyoung Joon Choi and T. Devereaux and E. Rotenberg and C. Kim},
journal= {arXiv preprint arXiv:0903.0681},
year = {2009}
}
Comments
9 pages, 8 figures, accepted for publication in Phys. Rev. B