Heidelberg 2015 – wissenschaftliches Programm
A 11.4: Poster
Montag, 23. März 2015, 17:00–19:00, C/Foyer
Electron re-localization dynamics in Xenon clusters under intense XUV pump-probe excitation — •Mathias Arbeiter, Christian Peltz, and Thomas Fennel — University of Rostock, Germany
Intense and temporally structured X-ray - light fields enable the controlled generation of strongly coupled nonequilibrium cluster nanoplasma. Sub-picosecond relaxation dynamics within the cluster are revealed via the delay dependent charge states as demonstrated in recent femtosecond soft x-ray pump-probe experiments . Here we report a scheme based on local electron single-particle energy spectra that enables microscopic tracing of the underlying electron-relocalization processes in molecular dynamics simulations up to the strong-coupling regime . We show that recombination dynamics strongly depend on temperature and density of the system leading to a rapidly converging electron relocalization within a few picoseconds and most efficient recombination in the cluster core. A systematic pump-probe analysis reveals that electron re-localization provides a fingerprint of electron cooling and nanoplasma rarefaction through cluster expansion and yield delay-dependent ion charge states in good agreement with experiments. The applied analysis is not restricted to soft x-ray excitation of clusters but essential also for the infrared regime and high harmonic light sources.