Q-switching and frequency doubling of solid-state lasers by a single intracavity KTP crystal

The electrooptic characteristics of the KTP crystal are analyzed in detail and Q-switched operation of a diode-laser-pumped microchip Nd:YVO/sub 4/ laser is reported using an intracavity KTP crystal. The KTP was used also as a frequency-doubling crystal in type II phase matching for generating pulsed green beams. Low loss and high efficiency characteristics were realized by eliminating two components, i.e., a Q-switching or a frequency-doubling crystal and a polarizer, in comparison with the conventional frequency-doubling configuration. Up to 15.4 W peak output and 18-ns width green power was obtained with 760-mW pumping power on the Nd:YV/sub 4/ microchip, which corresponded to 616 times enhancement of the CW output power.>