端面泵浦热传导各向异性激光棒的温度场  

Temperature field characteristics of thermal conductive anisotropic laser rods by LD end-pumped

作　　者：李隆[1,2] 聂建萍[1] 史彭[1] 冯小娟[1] 甘安生[1] 

机构地区：[1]西安建筑科技大学理学院,陕西西安710055 [2]中国科学院物理研究所,北京100190

出　　处：《光学精密工程》2009年第12期2931-2938,共8页Optics and Precision Engineering

基　　金：国家973重点基础研究发展规划项目(No.2006CB910300);陕西省工业攻关资助项目(No.2008K05-15)

摘　　要：为了解决LD端面泵浦热传导各向异性激光介质产生的热效应问题,建立了端面绝热、侧面冷却的Nd∶YVO4晶体热模型。考虑到Nd∶YVO4为热传导各向异性材料,而光纤耦合LD输出光束有超高斯分布的特点,利用特征函数法和常数变异法得到了超高斯光束端面泵浦热传导各向异性激光介质温度场的一般解析表达式,并定量分析了超高斯泵浦光阶次、泵浦功率以及光斑尺寸对Nd∶YVO4晶体温度场的影响。研究结果表明,若LD输出功率为50W,光学聚焦耦合器的传输效率为82%,用四阶超高斯光束端面泵浦掺钕离子质量分数为0.5%的Nd∶YVO4晶体时,泵浦面可获得528.95℃的最大温升。所得结果可用于LD端面泵浦热传导各向异性激光介质全固态激光器热稳腔的设计,对于提高激光器性能具有理论指导作用。With the aim to solve the thermal effect problem of thermal conductive anisotropic laser media end-pumped by LD, a thermal model of Nd ：YVO4 crystal with adiabatic end faces and a cooling circumference was established. As the Nd ： YVO4 crystal is a thermal conductive anisotropic material and the output beam of the fiber-coupled LD has the characteristics of super-Gaussian distrihution, a general analytical temperature field expression of the thermal conductive anisotropic laser medium end pumped by the super-Gaussian beam was obtained by the methods of eigen-funetion and constant variation. Meanwhile, the influences of the super-Gaussian beam with different orders, spot radius and powers on the temperature field of the Nd ： YVO4 crystal were quantitatively analyzed. The results show that when the output power of LD is 50 W and the transmission efficiency of the optical focusing coupler is 82%,the end-face of the Nd ： YVO4 crystal （the weight percent of neodymium ion doped in the crystal is 0.5%） end-pumped by the forth order super-Gaussian beam can get a maximum temperature rise of 528.95℃ The results can be applied to the design of thermally stabilized cavity of the all-solid-state laser with thermal conductive anisotropic laser medium end-pumped by LD, and will play theoretically a directional role in improving the performance of lasers.

关 键 词：固体激光器 各向异性介质 激光棒 ND∶YVO4晶体 温度场 

分 类 号：TN244[电子电信—物理电子学]