Fig. 1. Schematic illustration of the synchronization of the 100-PW laser and XFEL.

Fig. 2. (a) An overview of the synchronization for the seed and preamplifier. OPA, optic parametric amplification; HCF, hollow core fiber. (b) Timing measurement and feedback control links. MPC, multi-pass cavity; M1–M8, mirrors; CM1, CM2, chirped mirrors; DL, delay line; BOC, balanced optical cross-correlator. (c) Schematic of the noncollinear BOC. M, mirror; BS, beam splitter; GP, glass plate; BBO, beta barium borate crystal; BPD, balanced photodetector.

Fig. 3. Regenerative amplifier timing drift measurement results without the MPC for more than 5 hours: (a) in-loop timing drift, (b) DL control signal and (c) environment temperature fluctuation. (d)–(f) The measurement results of the in-loop timing drift, DL control signal, and temperature variation over 5 hours with the MPC in the optical path, respectively.

Fig. 4. Timing drift measurement of the 200-TW preamplifier over 120 minutes. (a) In-loop timing drift, (b) DL control signal and (c) environment temperature fluctuation.