Aufbau einer neuen XUV-Quelle und 2D Simulation von Wellenpaketdynamik in H⁺₂ -Molekülen

Abstract

The development of ultrafast Lasers gave rise to new possibilities in observing molecular motion and achieving high eld intensities. One application of such intensities is the generation of coherent light in the XUV and soft x-ray regime through high harmonic generation. In this work, a new HHG source using a gas lled hollow core ber is built and characterized. The waveguide allows phase matching over a long interaction range and therefore promises a high photon ux and tuning of the harmonic orders. The recorded photo electron spectra showed a weak dependence on the pressure of the gas, but no increase in the photon ux could be observed. In addition, a 2d quantum simulation of the wave-packet dynamics in H+2 was performed. The time evolution of the Schrodinger equation for two potential energy curves was calculated using a split-step operator technique. The two states are coupled via an external laser eld. The momentum distribution of the fragmented ions is measured in a pump-probe experiment using a reaction microscope and the simulation shows good agreement with the experimental results. Furthermore, a weak angle dependent dynamic was discovered in comparison with a 1d simulation. A classical calculation provides some insight into this mechanism but further investigation is required