Laser, Passively Q-Switched With a :ZnSe Saturable Absorber

We demonstrate efficient passively Q-switched laser operation, based on $\hbox{Tm}^{3+}\hbox{:LiGdF}_{4}$ and $\hbox{Cr}^{2+} $ :ZnSe, as active medium and saturable absorber, respectively. The polarized emission was centered at 1876 nm, with pulse parameters of 13 ns (duration), 467 $\mu\hbox{J} $ (energy), and 37 kW (peak power) at a repetition rate of 350 Hz.