High average power and high pulse energy nanosecond Ho:YAG MOPA laser pumped by a bulk Tm:YLF laser

In this work, a high average power and high single pulse energy Ho:YAG master oscillator and power amplifier laser system with a bulk Tm:YLF dual-pump structure was demonstrated at room temperature. At pulse repetition frequency of 3 kHz, as high as 260 W average power, corresponding to a single pulse energy of 86.7 mJ, was experimentally produced with optical-to-optical efficiency of 43.3% and pulse width of 28.1 ns. In addition, the laser central wavelength is ∼2090.4nm, and the beam quality factor M² is less than 1.8.