371~385 nm可调谐翠绿宝石连续激光器  

371-385 nm tunable alexandrite continuous-wave laser

作　　者：李奇 王金艳 季鑫 王斌 陈曦 郑权 Li Qi;Wang Jinyan;Ji Xin;Wang Bin;Chen Xi;Zheng Quan(Changchun New Industries Optoelectronics Technology Co.,Ltd,Changchun 130103,China;Changchun Institute of Optics,Fine Mechanics and Physics,Chinese Academy of Sciences,Changchun 130033,China)

机构地区：[1]长春新产业光电技术有限公司,吉林长春130103 [2]中国科学院长春光学精密机械与物理研究所,吉林长春130033

出　　处：《红外与激光工程》2023年第11期24-29,共6页Infrared and Laser Engineering

基　　金：吉林省重点研发计划项目(20220201088GX)。

摘　　要：371~385 nm波段的紫外激光器可以应用在超精密材料加工、激光多普勒冷却、光子纠缠和量子通讯等诸多领域。为实现这一波段激光输出,报道了一台可调谐翠绿宝石连续紫外激光器。首先,采用了水平偏振的635 nm红光半导体激光二极管阵列作为抽运源。其次,选用V型折叠腔结构,端面泵浦了长度为10 mm、Cr^(3+)掺杂浓度为0.2at.%的国产翠绿宝石晶体,再利用长度为7 mm的Ⅰ类位相匹配偏硼酸钡晶体进行腔内倍频。最后,微调节BBO晶体角度,实现了波长可连续调谐的371~385 nm连续运转的紫外激光输出。当泵浦光功率为17 W时,在波长为378 nm处得到最大稳定输出功率为1.25 W,泵浦光到紫外光的最大转换效率约为7.3%,波长为378 nm紫外激光光束质量因子沿着x和y方向分别为1.13和1.12。Objective Compared with all-solid-state UV lasers which use nonlinear crystals to perform tertiary or quadruple harmonic conversion of infrared light,the alexandrite lasers can obtain ultraviolet lasers by single frequency doubling.It has the characteristics of superior broadband emission spectrum which enables it to achieve tunable ultraviolet laser output.Therefore,tunable continuous ultraviolet laser plays an important role in applications.The ultraviolet 371-385 nm laser can be used in many fields,such as the ultra-precision material processing,laser Doppler cooling,entangled photon pair generation and quantum communication.Therefore,developing the tunable continuous ultraviolet laser has a great research value.Methods In order to achieve the laser output in the wavelength range of 371-385 nm,a tunable alexandrite continuous laser was developed.The experimental structure is a V-folded cavity and the length of the cavity is about 13 cm.A fiber-coupled 635 nm LD(Changchun New Industry Optoelectronic Technology Co.,Ltd)with the polarization ratio of greater than 100:1 is used as the pump source.The maximum pump power is 17 W.A caxis-cut alexandrite crystal with Brewster angle,a size of 3 mm×3 mm×10 mm and Cr^(3+)doping concentration of0.2 at.%,was used as the gain medium.It is wrapped with an indium foil and mounted in a water-cooled heat sink.A type-I phase-matched β-BaB_(2)O_(4)(BBO,θ=31°,φ=0°)with the size of 3 mm×3 mm×7 mm was used as the frequency doubling crystal.In the experiment,the polarization direction of the pump beam was adjusted by a halfwave plate to match the maximum absorption direction(the b axis)of the crystal.The optimization of the resonator mirror coating and the theoretical simulation cavity length reduce the loss of resonator and improve the conversion efficiency.The continuous tunable ultraviolet laser output at 371-385 nm is realized by adjusting the BBO angle.Results and Discussions The experimental schematic of the ultraviolet tunable alexandrite laser is shown(Fig.1).The max

关 键 词：紫外连续激光器 371~385 nm可调谐激光 腔内倍频 翠绿宝石晶体 

分 类 号：TN248.1[电子电信—物理电子学]