The Role of Electron-electron Interactions in Graphene ARPES Spectra

Marco Polini, Reza Asgari, Giovanni Borghi, Yafis Barlas, T. Pereg-Barnea, A. H. MacDonald

Published 2007-07-28Version 1

We report on a theoretical study of the influence of electron-electron interactions on ARPES spectra in graphene that is based on the random-phase-approximation and on graphene's massless Dirac equation continuum model. We find that level repulsion between quasiparticle and plasmaron resonances gives rise to a gap-like feature at small k. ARPES spectra are sensitive to the electron-electron interaction coupling strength $\alpha_{\rm gr}$ and might enable an experimental determination of this material parameter.