München 2019 – wissenschaftliches Programm
P 18.73: Poster
Donnerstag, 21. März 2019, 16:30–18:30, Foyer Audimax
Reflection Phase Shift Measurements at Developing Plasma Layers — •Nico Potzkai, Michael Stumpf, Julian Wegner, and Georg Pretzler — Institut für Laser- und Plasmaphysik, Heinrich-Heine-Universität Düsseldorf
The reflection phase change of light depends on the optical parameters of the reflecting material and can be calculated using Fresnel's equations with complex refractive indices. We measured this phase jump for the reflection at thin plasma layers at a solid surface. The plasma was generated by ultrashort laser pulses, and the measurement was performed with an extreme time resolution in the range of 10 fs, which allows conclusions on the freshly generated and evolving plasma. The experiments were done with different materials for plasma generation and also for the reflection at thin metal layers for comparison. We discuss first experimental results together with simulations showing dependences on the layer thickness and on the plasma parameters.