| Popis: |
This work aimed to provide advanced control over the focal spot of the PHELIX laser by the means of implementing a post-compressor adaptive optics loop. The ultimate goal was to increase the peak intensity on the target, which is critical for a lot of experiments that are based on laser-plasma interaction. Over the course of this thesis, I implemented an ultra-compact wavefront sensor, which could successfully measure the wavefront over the full 28 cm aperture of the PHELIX laser on a footprint of 2×1 meters for the full energy range of PHELIX. This sensor was used to run a closed control loop with a commercial deformable mirror. Furthermore, I developed a calibration routine for the sensor, which enabled finding the optimum achivable wavefront at the focal spot in the target chamber. Together with this routine, I was able to triple the intensity on target up to 1.4·10²¹ W/cm². This was the first time where an intensity of more than 10²¹ W/cm² could be reached systematically at PHELIX. Lastly, we performed an experiment in the group which provided a qualitative prove of the on-shot intensity gain by observing the transmission of the laser pulse through polystyrene foils of various thicknesses. The result verified the successful optimization of the peak intensity. |
