Passively Q-switched Nd:YVO_4 laser with a Cr^4+:YAG crystal saturable absorber

Abstract
We demonstrate, for the first time as far as we know, a passively Q-switched operation of a Nd:YVO4 laser in which a Cr4+:YAG crystal and a laser-diode bar are used as the saturable absorber and the pump source, respectively. Stable laser pulses as short as 28 ns with 20-µJ energy can be generated with this laser, which has the advantages of simplicity, high efficiency, and good long-term stability.