Anisotropy of excitation and relaxation of photogenerated charge carriers in graphene


Anisotropy of excitation and relaxation of photogenerated charge carriers in graphene

Mittendorff, M.; Winzer, T.; Malic, E.; Knorr, A.; Berger, C.; de Heer, W. A.; Schneider, H.; Helm, M.; Winnerl, S.

We present pump-probe experiments on graphene, which reveal a pronounced dependence of the pump-induced transmission on the angle between pump and probe polarization. It reflects a strong anisotropy of the pump-induced occupation of photogenerated carriers in momentum space. Within 150 fs after excitation an isotropic carrier distribution is established. The experiments are well described by microscopic modelling, which identify carrier-phonon scattering to be the main relaxation mechanism giving rise to an isotropic carrier distribution.

Keywords: graphene; carrier-dynamics; anisotropy; collinear scattering

Permalink: https://www.hzdr.de/publications/Publ-20058
Publ.-Id: 20058