160W端面抽运正支混合腔板条激光器的研究  

160 W laser-diode end-pumped Nd:YVO_4 slab laser with positive branch hybrid resonator

作　　者：苑佳华 张恒利[1] 毛叶飞[1] 郝相龙[1] 邢冀川[1] 辛建国[1] 

机构地区：[1]北京理工大学光电学院,北京100081

出　　处：《物理学报》2016年第19期107-111,共5页Acta Physica Sinica

摘　　要：研究了LD端面抽运Nd:YVO_4板条晶体正支混合腔Innoslab结构的激光器.利用Innoslab激光器的功率升级简单的优点,采用尺寸为22 mm×10 mm×1 mm的大块Nd:YVO_4晶体,最终在抽运功率为462 W时,获得最大功率为160 W的连续激光输出,功率波动为2.6%,光-光转换效率和斜效率分别为41.5%和47.7%.在输出功率为145 W时,测得光束质量在稳腔和非稳腔方向上分别为2.21和1.37.In this paper, we present an experiment on a continuous-wave Nd：YVO4Innoslab laser diode-pumped at 808 nm.The LD stack is composed of six bars, with the central wavelength fixed at 808 nm by adjusting the cooling water temperature. The emission from each diode laser bar is individually collimated by micro lens, which is coupled into a coupling system. The coupling system includes a planar waveguide, four cylindrical lenses and a spherical lens. The planar waveguide is used to shape the emitting beams of LD to obtain uniform distribution. The coupling system leads to a pump power loss of ～ 12%. By the coupling system, we obtain a homogeneous pumping line of ～0.4 mm × 22 mm coupled into the 0.3 at. % Nd：YVO4（22 mm × 10 mm × 1 mm） crystal. The Nd：YVO4crystal is a-cut with c axis along22 mm direction. Indium foil is used for uniform thermal contact and cooling. The laser crystal is mounted between two water-cooled copper heat sinks with two large faces 22 mm × 10 mm. The heat conduction inside the laser crystal is quasionedimensional. The two 22 mm × 1 mm surfaces are polished and antireflectioncoated for the pump light and the laser light. Temperature of LD stack and laser crystal are controlled by cooling circulating water. The resonator consists of the input mirror（M1） and the output mirror（M2）. M1 is a concave mirror with a radius of R1 = 500 mm,which is coated for high refection（HR） at 1064 nm and high transmission（HT） at 808 nm. The output mirror（M2） is a cylindrical mirror with a radius of R2 =-350 mm, which is coated for HR at 1064 nm. M2 is cut and polished at one edge where the large beam exits. M1 and M2 constitute a stable resonator in vertical direction and off-axis unstable positive confocal resonator in the horizontal direction. In theory, the length of the resonator is L =（R1 ＋ R2）/2 = 75 mm. In fact, the length of the resonator is the same as the theoretical value. The equivalent transmission of the resonator is T = 1- ｜R2/R1｜ = 30%. At a pumping power

关 键 词：ND:YVO4晶体 正支混合腔 Innoslab 

分 类 号：TN248[电子电信—物理电子学]