WSe₂ as a saturable absorber for a passively Q-switched Ho,Pr:LLF laser at 295 µm

Multilayer WSe2 films were prepared by the liquid-phase exfoliation method and dispersed onto a YAG substrate. The obtained WSe2-SA was used to investigate a passively Q-switched Ho,Pr:LLF laser at 2.95 µm. Under an absorbed pump power of 4.51 W, the shortest pulse duration of 571 ns was realized with an average output power of 147 mW and a repetition rate of 89.3 kHz, corresponding to a single pulse energy of 1.65 µJ and a peak power of 2.88 W. The results indicate that WSe2 is a promising candidate for application as a saturable absorber to generate mid-IR pulsed lasers at ~3 µm.