Efficient, kHz repetition rate, gain-switched Cr : forsterite laser

We have developed a gain-switched room-temperature Cr:forsterite laser oper ating at repetition rates of between 1 and 34kHz, and pumped by a continuou s wave, Q-switched Nd:YAG laser. With optimised output coupling, an output pulse energy of 52 mu J was measured at 1.5 kHz repetition rate, correspond ing to 11% efficiency and 13% slope efficiency. Threshold pulse energy was 53 mu J. Output power of 370 mW was obtained at 10 kHz repetition rate and 4.4W pump power. Water cooling was not required for repetition rates up to 10 kHz. In a tunable, folded resonator, the Cr:forsterite wavelength tuned between 1173 and 1338 nm. This laser operated with maximum pulse energy of 34 mu J, efficiency of 13%, and power of 307 mW. The laser output was close to diffraction-limited with M-2 of 1.2.