A high-energy acousto-optic Q-switched dual-crystal Tm:YAP laser at 1 kHz repetition rate was investigated. Using two b-cut Tm:YAP crystals in an L-shaped resonator with laser diode dual-end pumped at 793 nm, a pulse energy of 22.31 mJ at 1938.86 nm with 0.19 nm linewidth was achieved, corresponding to a 65 ns pulse width and 343.2 kW peak power, with beam quality factor M 2 ~ 3.4. In addition, when the pump power was 137.4 W, an average power of 29.96 W was obtained in continuous wave mode. To the best of our knowledge, this work represents the highest pulse energy reported of acousto-optic Q-switched Tm:YAP oscillator lasers at 1.94 μm.
Gao et al. (Sat,) studied this question.