Self-Q-switched Nd:YVO/sub 4/ microchip lasers

Summary form only given. Microchip lasers are typically formed by applying dielectric mirrors directly to two near-parallel surfaces of a thin slice of laser gain material. Nd:YVO/sub 4/ is a commonly used gain material because of its short absorption depth and high stimulated emission cross section. While working on gain-switched Nd:YVO/sub 4/ microchip lasers, we observed in these monolithic devices large spiking behavior, which could not be accounted for by normal gain-switching theory. Gain switching can produce peak powers in excess of a watt, several times the cw level, with pulses as short as 5 ns. However, the large spikes we observed were several hundred times the cw level with peak powers >25 W and pulses as short as 1.85 ns, more similar in nature to Q-switched pulses. We have constructed a simple model to include this effect in determining the stability of a microchip laser. The results of this model are presented in comparison to the observed experimental work, to show how the effects of gain-related cavity stability can cause self-Q-switching in a Nd:YVO/sub 4/ microchip laser.