A highly efficient milli-joule-level Q-switched Tm,La:CaF2 laser is experimentally demonstrated. By employing an acousto-optic modulator, the diode-pumped pulsed lasers are stably operated at repetition rates ranging from 500 Hz to 10 kHz. Dual-wavelength operation of 1881.7 nm and 1888.5 nm is achieved with slope efficiency of 64.7%. Up to 1.89 mJ of pulse energy is obtained at a pulse width of 100 ns, corresponding to a peak power of 18.88 kW. These results verified that the Tm,La:CaF2 crystal could be a promising candidate for achieving highly efficient and high-energy pulsed lasers.

We report on laser diode (LD) pumped passively Q-switched Yb,Gd:SrF₂ lasers with high single-pulse energy for the first time, to the best of our knowledge. In addition, a stable Q-switched laser based on a Cr⁴⁺:Y₃Al₅O₁₂ saturable absorber was demonstrated. The maximum output power of the Q-switched laser obtained was 495 mW, with a pulse width and a pulse repetition rate of 233 ns and 1.238 kHz, respectively. The corresponding single-pulse energy and the peak power were as high as 400 μJ and 1.714 kW. The laser was operated under a transverse electromagnetic mode, and the beam quality was near-diffraction-limited.