879nm直接抽运提高Nd∶GdVO_4激光器性能

激光二极管(LD)大功率端面抽运固体激光器(DPSSL)中的热效应会影响到激光器的各个方面,使得激光输出效率下降,光束质量变坏、谐振腔的稳定性变差等。采用新波段879 nm取代808 nm,将粒子直接激励到激光发射上能级,降低无辐射弛豫过程产生的热量,有效地减少热的产生,降低激光二极管端面抽运Nd∶GdVO4晶体的热效应,获得更高性能的激光输出。在相同条件下通过879 nm激光二极管直接端面抽运及808 nm激光二极管间接端面抽运Nd∶GdVO4激光器的实验比较,结果表明,在较高抽运功率下采用879 nm抽运提高了Nd∶GdVO4激光器的激光输出性能。最后采用879 nm激光二极管端面抽运Nd∶GdVO4晶体棒直线腔方案,在16.3 W的吸收抽运功率下,获得最大连续输出功率9.8 W的TEM00模1063 nm激光输出,对吸收抽运光的光-光转换效率高达60.1%,斜率效率达68.4%。

Performance Improvement of Nd∶GdVO4Laser under 879 nm Direct Pumping

Thermal effect in the laser diode (LD) high-power pumped solid-state lasers will reduce the efficiency of output power, decrease the output beam quality, deteriorate the resonator stability and so on. The novel 879 nm LD instead of 808 nm LD was used to pump Nd∶GdVO4 crystal rod directly, driving Nd3+ ions into the laser emitting level, avoiding useless heat generation during no-radiation transition and reducing the thermal effects efficiently. In the same experimental conditions, the comparison on performances of Nd∶GdVO4 laser between under 808 nm LD pumping and under 879 nm LD pumping was demonstrated, and showed that the performances of the former were superior to that of the latter. In the 879 nm LD pumped Nd∶GdVO4 plane-plane cavity laser, the maximum TEM00 1063 nm output power of 9.8 W is obtained at an absorbed pump power of 16.3 W, an optical-optical efficiency of 60.1% and a slope efficiency of 68.4% are achieved.