Actively Q-switched intracavity second-harmonic generation of in BiB3O6 crystal

Abstract We have investigated the acousto-optically Q -switched intracavity second-harmonic generation of 1.06 μm in a 1.9-mm-long BiB 3 O 6 crystal, cut for type-I phase-matching direction of ( θ , ϕ )=(168.9°,90°), performed in a diode-end-pumped Nd:YVO 4 laser. When the incident pump power was 4.3 W at 30 kHz of pulse repetition frequency, a maximum average green output power of 480 mW , the shortest pulse with FWHM width of 72 ns , the highest single pulse energy of 16 μJ and the maximum peak power of 222 W were obtained, giving the corresponding optical conversion efficiency of 11.2%. The effect of varying temperature in BIBO crystal on the average green output power was also investigated.