Plasmons and the spectral function of graphene

Abstract

We report a theoretical study of the influence of electron-electron interactions on the one-particle Green's function of a doped graphene sheet based on the random-phase approximation and on graphene's massless Dirac equation continuum model. We find that states near the Dirac point interact strongly with plasmons with a characteristic frequency ${\ensuremath{\omega}}_{\mathrm{pl}}^{\ensuremath{\star}}$ that scales with the sheet's Fermi energy and depends on its interaction coupling constant ${\ensuremath{\alpha}}_{\mathrm{gr}}$, partially explaining prominent features of recent angle-resolved photoemission spectroscopy data.