Characterization measurements of the laser system. (a) Amplification slope of the multipass amplifier. The measured output power is plotted as a function of the seed power. (b) Near-field beam profile of the uncompressed output of the multipass amplifier. (c) Measured autocorrelation trace of the compressed output pulses at 720 mJ pulse energy. Assuming a Gaussian temporal pulse shape, the pulse duration is 1 ps. (d) Near-field beam profile of the compressed output.