Phonon-induced linewidths of graphene electronic states

Abstract

The linewidths of the electronic bands originating from the electron-phonon coupling in graphene are analyzed based on model tight-binding calculations and experimental angle-resolved photoemission spectroscopy (ARPES) data. Our calculations confirm the prediction that the high-energy optical phonons provide the most essential contribution to the phonon-induced linewidth of the two upper occupied $\ddot{I}ƒ$ bands near the $\bar{\hat{I}}“$-point. For larger binding energies of these bands, as well as for the $\ddot{I}€$ band, we find evidence for a substantial lifetime broadening from interband scattering $\ddot{I}€\to \ddot{I}ƒ$ and $\ddot{I}ƒ\to \ddot{I}€$, respectively, driven by the out-of-plane ZA acoustic phonons. The essential features of the calculated $\ddot{I}ƒ$ band linewidths are in agreement with recent published ARPES data [F. Mazzola et al., Phys.~Rev.~B. 95, 075430 (2017)] and of the $\ddot{I}€$ band linewidth with ARPES data presented here.

7 pages, 4 figures