Minjian Wu, Hailong Zhang, Yixing Geng, Olivier Chalus, G. Rey, Alain Pellegrina, Philippe Fichot, Vincent Leroux, Chang Liu, Yanying Zhao, Xueqing Yan
In this paper, we report the recent progress on the 2 PW/1 Hz laser system for laser-driven proton tumor therapy facility CLAPA-II [Kedong et al., Phys. Rev. Accel. Beams 23, 111302 (2020)], and the system is currently capable of outputting a maximum single-pulse laser energy of 71.9 J, a pulse width of 29 fs, and a peak power of 2.48 PW for high-power fs lasers. In terms of laser quality parameters, ps contrast is better than 1012, and ns contrast is 2 × 1010. In terms of laser stability, the horizontal and vertical angular pointing fluctuations over 500 shots were measured to be 1.04 and 0.797 μrad, respectively. The device has currently been deployed in laser acceleration experiments.