Simulation of femtosecond laser induced electron excitation in a Multi-Layer Dielectric (MLD) grating

The pulse compression grating (PCG) is one of the most critical components of a high power chirped pulse amplification laser system to achieve the shortest pulse duration. Compared to metal gratings, a multi-layer dielectric (MLD) grating is a possible solution to improve the laser induced damage threshold (LIDT) of PCGs. Our previous work reported simulations of electron excitation dynamics in the interaction of MLD mirrors and femtosecond pulses (<100 fs). Here we present the study of the interaction of a MLD grating and a 50-fs pulse using a 2D dynamic simulation modeling both the E-field enhancement and transient material responses.