Theoretical study of time-resolved photoemission of graphite near Brillouin zone K and H points

The time-resolved photoemission spectra of graphite near the Brillouin zone K and H points are obtained by the many-body time-dependent approach, where the nonradiative relaxation process of the excited electron by the phonon release is considered. The relaxation of the spectral weight is highly suppressed near the H point compared to the K point. This implies that the effective electron-phonon coupling near the K point is stronger than that near the H point.