连续LD端面泵浦YAG/Yb∶YAG复合晶体温度场分析  

Temperature Field of Continuous LD End-Pumped YAG/Yb∶YAG Composite Crystal

作　　者：李隆[1,2] 牛娟 张春玲 杨建花[1] 薛彪 耿鹰鸽 Li Long;Niu Juan;Zhang Chunling;Yang Jianhua;Xue Biao;Geng Yingge(Faculty of Science,Xi'an University of Architecture and Technology,Xi'an 710055,Shaanxi,China;Institute for Applied Physics,Xi'an University of Architecture and Technology,Xi'an 710055,Shaanxi,China)

机构地区：[1]西安建筑科技大学理学院,陕西西安710055 [2]西安建筑科技大学应用物理研究所,陕西西安710055

出　　处：《激光与光电子学进展》2022年第13期277-282,共6页Laser & Optoelectronics Progress

基　　金：国家自然科学基金(11705136)。

摘　　要：为了解决激光二极管端面泵浦圆盘晶体引起的热效应问题,根据连续LD端面泵浦圆盘形YAG/Yb∶YAG的工作特点,基于热传导理论建立了复合晶体有限元分析模型。通过设定LD泵浦参数,定量分析了泵浦功率、复合晶体厚度与截面大小对温度场的影响。研究结果表明,当复合晶体几何结构一定时,随泵浦功率增大,晶体温度升高。当泵浦功率为70 W,经光学耦合系统准直聚焦的泵浦光斑半径为400μm时,Yb∶YAG晶体厚度为3 mm,当键合的YAG晶体厚度从0 mm变为0.7 mm时,复合晶体内最高径向温升降低了39.7℃,最高轴向温升降低了238.3℃。在相同泵浦条件下,取YAG晶体厚度为0.5 mm,当复合晶体截面半径由8 mm增加至13 mm时,晶体内沿径向的最高温升降低了32.8℃,沿轴向最高温升降低了171.7℃。利用复合晶体能够降低激光晶体内部热效应,对实现全固态Yb∶YAG激光器高功率输出具有指导意义。In this paper,we proposed a finite element model of composite crystals to solve the thermal effect of disk crystal end-pumped by LD.The model was established based on the heat conduction theory,which is related to the working characteristics of continuous LD end-pumped YAG/Yb∶YAG disk.The effects of different factors such as the pump power,composite crystal thickness,and cross section size on the temperature field were analyzed by setting LD pumping parameters.The results showed that when the geometry of the composite crystal is constant,the temperature of the crystal increased with increasing pump power.At 70 W pump power,the pump spot radius was 400μm via the collimation focusing of the optical coupling system,the thickness of Yb∶YAG crystal was 3 mm,and the thickness bonding of YAG crystal changed from 0 mm to 0.7 mm.Furthermore,the rise in maximum radial and axial temperatures decreased by 39.7℃ and 238.3℃,respectively.Under the same pumping conditions and with a 0.5 mm thick YAG crystal,the cross section radius of composite crystal increased from 8 mm to 13 mm,the maximum temperature rise along the radial and axial directions decreased by 32.8℃and 171.7℃,respectively.Thus,the composite crystals can reduce the thermal effect inside laser crystals,which is significant for realizing high-power outputs of solid-state Yb∶YAG lasers.

关 键 词：激光器 激光二极管 YAG/Yb∶YAG 复合晶体 温度场 

分 类 号：O434[机械工程—光学工程]