High average power OPCPA MIR-systems for coherent soft Ⅹ-ray generation accessing absorption edges of metals

摘要

Two OPCPA-systems at central wavelengths of 2.1 μm (in operation) and 3.1 μm (under construction) provide pulses with a temporal duration of 4 cycles at a pulse repetition rate of 10 kHz and an average power of about 30 W. Both systems feature a single pump laser design with a powerful thin disk Yb:YAG pumplaser. Concept, simulation and beam emission characteristics are discussed. Flux levels in high harmonic generation of ~10~9 photons/eV/s @ 150 eV, ~10~7 photons/eV/s @ 350 eV and ~10~6 photons/eV/s @ 450 eV have been determined with absolutely calibrated measurement tools. An IR-pump - soft Ⅹ-ray scattering probe experiment at the Gd N-edge (150 eV) employing the transversal magnetic optical Kerr effect (TMOKE) investigates dynamics of optical magnetic switching and serves as a benchmark for future studies.