Spectral pulse shaping of a 5 Hz, multi-joule, broadband optical parametric chirped pulse amplification frontend for a 10 PW laser system.

Abstract

We present a broadband optical parametric chirped pulse amplification (OPCPA) system delivering 4J pulses at a repetition rate of 5Hz. It will serve as a frontend for the 1.5kJ, <150 fs, 10PW laser beamline currently under development by a consortium of National Energetics and Ekspla. The spectrum of the OPCPA system is precisely controlled by arbitrarily generated waveforms of the pump lasers. To fully exploit the high flexibility of the frontend, we have developed a 1D model of the system and an optimization algorithm that predicts suitable pump waveform settings for a desired output spectrum. The OPCPA system is shown to have high efficiency, a high-quality top-hat beam profile, and an output spectrum demonstrated to be shaped consistently with the theoretical model.