For our next talk in our online seminar series, we welcome yLudger Wirtz and Thomas Deckert from the University of Luxembourg. Please contact Katharina to get the link to the online talk.

05.05. Talk No.10

15-15:10 Ludger Wirtz: Studying at the University of Luxembourg

15:10 – 15:45 Thomas Deckert, Ultrafast Coherent 2D Spectroscopy at Visible and Mid Infrared Frequencies

15:45 – 16:00 discussion

Abstract:

Ultrafast Coherent 2D Spectroscopy at Visible and Mid Infrared Frequencies

Energetic correlations and their dynamics govern the fundamental properties of condensed matter systems. Therein, ultrafast spectroscopy is an established technique for the investigation of such dynamics upon an impulsive photoexcitation. However, the broadband nature of ultrafast pulses intrinsically prevents precise energy resolution of the excitation process, unless a sequence of three or more pulses is employed in the framework of ultrafast two-dimensional (2D) spectroscopy. While the technique has been widely used to study the coupling of molecular resonances in the infrared, its application to femtosecond dynamics of solid-state materials is still new. After introducing the general concept of 2D spectroscopy, we will discuss our recent results on a wide- and low-bandgap semiconductor, showing the disentanglement of free carrier and exciton dynamics in gallium selenide as well as high-order nonlinear spectroscopy signals and coherent effects in indium antimonide, respectively.