231 W dual-end-pumped Ho: YAG MOPA system and its application to a mid-infrared ZGP OPO

A high-efficiency and high-brightness Ho:YAG master-oscillator power-amplifier (MOPA) systemdual-end pumped by Tm:YLF lasers was demonstrated. The maximum output power of 231 W at a wavelength of 2090.7 nm was achieved with pulse repetition frequency of 10 kHz and pulse width of 22.9 ns, corresponding to pulse energy of 23.1 mJ and peak power of similar to 1 MW. The extraction efficiency of the amplifier system was more than 60%. The beam quality factor M-2 was measured to be similar to 1.05. Using the Ho: YAG MOPA system as the pump source, the ZnGeP2 optical parametric oscillator delivered an output power of 110 W, corresponding to slope efficiency of 62%. (C) 2018 Optical Society of America