Code for simulation of the spatial and temporal transformation of femtosecond laser pulses induced by optical systems

Summary form only given. One of the important issue in high intensity CPA chains, is the determination of the output pulse duration. The seed pulse is modified through the CPA amplification by different processes (dispersion through amplifying materials, spatial and temporal transformation through lenses or other optical components...) and it is often difficult to predict the pulse duration after compression. This duration can be measured with techniques such as spider or autocorrelators, but to design such complex systems, it is of crucial importance to be able to foresee what the pulse duration should be. Moreover spatio-temporal effects are often neglected for ultrashort pulses and however strongly modify the temporal characteristics of the laser pulse on interaction targets. We present a set of simulations of stretchers-compressors systems including dispersive beam expanders and show for pulses shorter than 30 femtoseconds how crucial are these spatio-temporal coupling effects.