111 W picosecond Ho:YAG amplifier and its application to 10 μm mid-infrared generation

In this Letter, we report a high-power picosecond Ho:YAG amplifier system delivering an average output power exceeding 111 W at a repetition rate of 10 kHz, achieving an overall gain of 93 dB, with beam quality characterized by <i>M</i>² values of 1.53 and 1.65 in two orthogonal directions and highly stable operation (1.7% RMS fluctuation). To the best of our knowledge, this represents the highest average power demonstrated thus far for a 2-μm picosecond laser amplifier. Utilizing this robust amplifier as a pump source, we further developed a ZnGeP₂ (ZGP) optical parametric generator (OPG) for mid-infrared radiation, successfully achieving direct emission at 10.1 μm with an output power of 123 mW under a pump power of 16 W. Notably, this work demonstrates the first direct 10 μm generation from a ZGP-based OPG.