Cryogenic Yb：YAG solid state pulsed laser amplifier

Compared with Nd:YAG, the Yb:YAG laser system is more suitable to produce at several Hz repetition rates high pulsed energy laser beam. A LD pumped Yb:YAG solid state pulsed MOPA laser system at cryogenic temperature was reported. The amplifier chain was composed of three parts: regenerative amplifier seed, pre-amplifier and main amplifier. The thermal management was realized by liquid nitrogen cooling sink on which laser crystal was compressed using indium and gold foil as thermal interface. The coating film damage at cryogenic and vacuum environment was studied, which directly affected the pumped and extracted parameter design. A 1 030 nm pulse 10 Hz, 10 ns laser output energy 3 J was achieved. At last, in order to improve laser energy scalability the further step was analyzed.