Regensburg 2019 – wissenschaftliches Programm
O 63.1: Poster
Mittwoch, 3. April 2019, 17:45–20:00, Poster B1
Electron dynamics in MoS2 after resonant optical excitation probed with different light polarizations — •Lasse Münster, Robert Wallauer, Johannes Reimann, Jens Güdde, and Ulrich Höfer — Fachbereich Physik und Zentrum für Materialwissenschaften, Philipps-Universität, 35032 Marburg
We will report on the application of time- and angle-resolved two photon photoemission (2PPE) with a high harmonic probe for the investigation of electron dynamics of MoS2 in momentum space. For this purpose, we combined a high-repetition rate high-harmonic source with tunable femtosecond pump pulses and a 3D (kx, ky, E) electrostatic electron spectrometer .
We used this setup to study the electron dynamics in the conduction band of MoS2 after resonant optical excitation at the K-point with different polarizations of pump- and probe pulses. In addition to the excitation into the conduction band, we observe non-resonant 2PPE from the valence band which can be suppressed by using cross-polarized pump and probe pulses. Within our time-resolution of better than 50 fs, we observe an instantaneous occupation of the conduction band at K followed by an ultrafast transfer to the conduction band minimum at Σ.
 R. Wallauer et al., Appl. Phys. Lett. 109, 162102(2016).