Pump-Probe Methods

Our tool of choice for measuring dynamic processes that take place on ultrashort time scales is a time-resolved type of measurement the so-called pump-probe technique. Here one promotes the system in a highly non-equilibrium state by optical excitation with an intense pump pulse and monitors the subsequent transient dynamics by a time-delayed, weaker probe pulse. Such time domain measurements offer direct information about the time evolution of the system down to few femtoseconds time scale.

At the Femtoslicing facility one can use for pumping femtosecond laser pulses with photon energies covering the range from UV and VIS to mid-IR part of the spectrum and probe the subsequent sample dynamics with femtosecond or/and picosecond X-ray pulses covering the soft  X-ray range from 250 eV to 1400 eV. (Femtospex) At our institute, we conduct pump-probe experiments with a wide range of experimental techniques using ultrashort pulses of x-rays and UV/VUV radiation: