kJ-10 PW class laser system at 1 shot a minute (Conference Presentation)

State-of-the-art physics experiments are pushing the development of lasers with ultra-high peak power pulses. 4 PW pulses have been produced with TiSa [1] and 10 PW with the same gain medium is scheduled at LULI (Apollon) and at ELI-NP. The other approach is to use Nd-doped glass as gain medium, whose interest is in its capability of delivering higher energy at the expense of a longer pulse duration. Based on this gain material combined with an OPCPA based front-end, a kJ-10 PW class laser has been designed and built. The front-end, consisting of picosecond OPCPA, temporal pulse cleaning and nanosecond OPCPA, delivers pulses with excess of 4 Joules at 5 Hz with a shaped spectrum to pre-compensate for gain distortions in Nd:glass power amplifiers. Two liquid-cooled, mixed glass power amplifiers, namely PA1 and PA2, are used for further amplification. Up to now, they have been activated demonstrating 70 J at 1 shot a minute after PA1 and 1 kJ at 1 shot every 7 minutes for PA2. The Fourier limit of the spectrum is 150 fs meaning 6 PW capability after compression. This energy level has been obtained with only 3 Joules seed energy, from the OPCPA and partial activation of PA2. Scaling of this result suggests that more than 1.7 kJ should be obtained leading to 10 PW after compression while the output spectrum will remain compatible with 150 Fs thanks to the OPCPA spectral tailoring capability.