638 nm、532 nm 激光泵浦的连续波翠绿宝石激光器

报道了一种高功率、高光束质量的755 nm连续波翠绿宝石激光器。首先，对比研究了638 nm激光二极管（LDs）和532 nm固体激光器单端泵浦的翠绿宝石激光器。当638 nm LDs作为泵浦源时，得到的连续输出功率、光-光转换效率分别为3.9 W和19.7%。保持其他条件基本不变，将泵浦源换成532 nm激光器，得到的连续输出功率、光-光转换效率分别为2.1 W和10.0%。结果表明利用 638 nm LDs泵浦翠绿宝石可获得更高的激光功率和转换效率。此外，研究了638 nm LDs双端泵浦的翠绿宝石激光器，在755 nm处得到了6.2 W的连续输出功率，相应的光-光转换效率和斜效率分别为16.3%和24.2%，并且连续输出功率为5.0 W时的光束质量M2优于1.47，这是翠绿宝石激光器在近衍射极限下的最高连续输出功率。这种高功率、高光束质量的755 nm翠绿宝石激光器为连续波紫外激光器的研制提供了良好、稳定的基频源。

Continuous-wave Alexandrite laser pumped by 638nm and 532nm lasers

A high power 755 nm continuous-wave(CW)laser with high beam quality based on the Alexandrite crystal was demonstrated.The Alexandrite lasers single-end-pumped by 638 nm laser diodes(LDs)and 532 nm solid-state laser were studied comparatively,then the CW output power,optical-to-optical conversion efficiency,and slope efficiency pumped by 638 nm LDs were 3.9 W,19.7%,and 23.7%,respectively,while they were 2.1 W,10.0%,and 12.9%,at nearly the same conditions except that it was pumped by 532 nm solid-state laser.The results show that the Alexandrite laser pumped with 638 nm LDs can obtain higher CW output power and higher conversion efficiency.Moreover,a CW output power of 6.2 W at 755 nm of Alexandrite laser double-endpumped by a 638 nm LDs was achieved with the optical-to-optical conversion efficiency and the slope efficiency of 16.3%and 24.2%,respectively.The beam quality factor M2 was better than 1.47 at the CW output power of5.0 W,which was the highest CW output power of Alexandrite laser with the diffraction limit to the best.This high power and high beam quality 755 nm Alexandrite laser provides the fundamental frequency source for the development of CW ultraviolet lasers.