Nd:LuYAG混晶1123nm被动调Q激光器

A diode pumped passively Q-switched Nd:LuYAG laser emitting at 1123 nm

文章报道了一个二极管激光抽运的1123 nm被动调Q激光器.激光晶体为混晶Nd:LuYAG,饱和吸收体选为Cr^(4+):YAG晶体.在连续运转情况下,最高输出功率为2.77 W,对应的光-光转换效率为29.53%.调Q运转时,在9.38 W吸收抽运功率下,最高输出功率为0.94 W.脉冲宽度整体在105 ns左右.在最高吸收抽运功率下,1123 nm激光的输出重复频率为9.40 kHz,对应的单脉冲能量可达100μJ,高于目前报道的单晶Nd:YAG 1123 nm单脉冲能量,证明其在能量存储方面较单晶Nd:YAG更具优势.另外,据我们所知,这是关于混晶Nd:LuYAG 1123 nm输出的首次报道.

A diode pumped passively Q-switched 1123 nm laser is reported in this paper; and a mixed crystal Nd：LuYAG is selected as the gain medium. A large number of excellent properties from Nd：YAG are obtained, and the mixed crystal Nd：LuYAG has been used widely in all-solid-state lasers. Besides, compared with Nd：YAG, the Nd：LuYAG has some other wonderful advantages. For example, both the absorption bands and the fluorescence line are broadened, resulting from the crystal strong inhomogeneity. Their wide absorption makes the Nd：LuYAG lasers’ pump source not rigorous in their temperature control. And the broadened fluorescence line can generally improve the laser performance in Q-switched regimes. In this paper, a concave-plane configuration cavity with its length as long as 35 mm is designed to achieve high-e？ciency laser output. The rear mirror is a concave mirror with a curvature radius of 300 mm, and the output coupler is a flat mirror with a transmission of 2% at 1123 nm, 5% at 1112 nm, 4% at 1116 nm, and has high transmissions at 1064, 1319 and 1444 nm respectively. A Cr^4＋：YAG crystal, with its initial transmission of 97%, is used as the saturable absorber. In the continuous wave operation, the maximum average output power can reach 2.77 W, with the corresponding optical-to-optical conversion efficiency of 29.53%. In Q-switched operation, the maximum average output power is 0.94 W at 9.38 W absorbed pump power. The repetition rate is 9.40 kHz, with the corresponding single pulse energy being 100 μJ. The high single-pulse energy explains that the Nd：LuYAG mixed crystal is better than Nd：YAG in high energy storage. Only one wavelength can be observed in our experiment. The center wavelength is 1122.7 nm and the line width is 0.03 nm. To the best of our knowledge, this is the first time to report the Nd：LuYAG mixed crystal laser emitting at 1123 nm.