40th International Workshop on High Energy Density Physics with Intense Ion and Laser Beams

The importance of a high laser contrast in laser-plasma experiments is widely known. While the temporal contrast in the nanosecond time scale is well understood and optimized, short pulse laser systems around the world still suffer from a slow rising slope of the peak and hence a worse contrast in the regime of picoseconds prior the peak intensity. We identified noise in a CPA stretcher to be the origin of this short timescale contrast degradation. We present simulations on the influence of different kinds of noise – e.g. dust or surface deformation – onto the spectral phase and therefore the temporal pulse shape. The simulation results are compared to measured pulse profile and recommendations for future stretcher designs are concluded.