Microchip laser operating at 1338 nm

Abstract

ABSTRACT Q-switched microchip laser emitting radiation at wavelength 1338nm was designed and realized. This laser wasbased on monolith crystal which combines in one piece a cooling undoped part (undoped YAG crystal, 4mm long),active laser part (YAG crystal doped with Nd 3+ ions, 12mm long) and saturable absorber (YAG crystal dopedwith V 3+ ions, 0.7mm long). The diameter of the diusion bounded monolith was 5mm. The initial transmissionof the V:YAG part was 85%. The microchip resonator consists of dielectric mirrors directly deposited on themonolith surfaces. The pump mirror (HT for pump radiation, HR for generated radiation) was placed on theundoped YAG part. The output coupler with re”ection 90% for the generated wavelength was placed on theV 3+ -doped part. Q-switched microchip laser was tested under pulsed, and CW diode pumping. The pulse lengthit was the same for all regimes equal to 6.2ns. The wavelength of linearly polarized laser emission was “xed to1338nm. The pulse energy depends on the mean pump power. For pulsed pumping the output pulse energy wasstable up to mean pump power 1W and it was equal to 135 µ J, which corresponds to peak power 22kW. In CWregime for pumping up to 14W the pulse energy was stabilized to 37 µ J (peak power 6kW). The mean outputpower increased up to 0.4W only by increase of the generated pulse repetition rate (11kHz for mean pump power14W).Keywords: Nd:YAG, V:YAG, diode-pumped laser, microchip laser