Developing ultrafast spectroscopic techniques with fs resolution from UV to mid infrared
Time-resolved Spectroscopy
Developing ultrafast spectroscopic techniques with fs resolution from UV to mid infrared.
We develop precise measurement setups in the sub-20-femtosecond regime. With the NOPArainbow, we have direct tunability between 380 nm and 1.6 µm with only a small gap at the fundamental. We can also access all wavelengths down to 190 nm, as well as into the MIR, with only a single nonlinear mixing process.
Intrinsic efficiency limits in low-bandgap non-fullerene acceptor organic solar cells Nature Materials (2021)
About this research area
For decades the limiting factor of a laser spectroscopy experiment was – true or not – often associated with the pump laser of the experiment. The latest generation of Yb-based femtosecond lasers now offers unprecedented pointing and energy stability. Therefore the excuses for the experimentalist disappear and it is solely the experimentalists' job to make even complex experiments work. The aim of our work is to develop precise measurement set-ups in the sub-20 femtosecond regime.
For that we require convenient and often real-time spectral and temporal diagnostics, which we usually develop ourselves. Those can be second harmonic or two-photon absorption based autocorrelators for real time pulse length measurements.
In terms of pump light generation, we are working with Prof. em. Dr. Eberhard Riedle on the continuous development of non-collinear optical parametric amplifiers (NOPA). With the introduction of the NOPArainbow, we have direct tunability between 380 nm and 1.6 µm with only a small gap at the fundamental. With only a single nonlinear mixing process we can access all wavelengths down to 190 nm as well as into the MIR. All set-ups are developed within our group to enable us to measure any dynamics.
Once running, we always aim for collaborations with other groups to test our developments in the field.
