München 2019 – wissenschaftliches Programm
P 18.72: Poster
Donnerstag, 21. März 2019, 16:30–18:30, Foyer Audimax
High-resolution Reflective Interferometry Experiments at a sub-10-fs Laser-produced Plasma — •Maximilian Münzberg, Michael Stumpf, Georg Pretzler, and Steffen Mittelmann — Institut für Laser- und Plasmaphysik, Heinrich-Heine-Universität Düsseldorf
We present results from an experiment in which ultrashort laser pulses (8 fs) were focused with maximum intensities of 2·1017 W/cm2 onto flat metallic surfaces. We measured the time evolution of the electron distribution by investigating the wave front deformation in the probe pulse with a Mach-Zehnder-Interferometer. Under some conditions we find two expansion phases - a fast one with a time scale of tens of femtoseconds and strong spatial variations and a ps-scale expansion which is almost isotropic. The experiments were performed with varied laser intensities and different target geometries. The experimental results are compared with PIC-simulations which verify a strong dependence of early expansion on the surface structure of the targets.