【摘要】 为解决激光二极管端面泵浦Yb:YAG复合晶体引起的热效应问题，通过分析复合晶体工作特点，建立了多个以不同方式键合的周边冷却恒温、端面与空气热交换的有限元热模型。基于热传导理论，利用泊松方程对不同复合方式的Yb:YAG复合晶体的温度场、应力场与热形变场进行数值计算，并对不同复合方式的Yb:YAG复合晶体在激光二极管端面泵浦时的温度场和形变量进行对比。研究结果表明，若激光二极管泵浦功率为50 W,耦合到泵浦面的光斑半径为400μm,键合方式为单端键合、键合长度为0.5 mm、Yb:YAG纯晶的尺寸为3 mm×3 mm×6 mm、掺杂浓度为5.0%的Yd:YAG晶体端面的最高温升为57.01 K,最大应力为1.067×10⁸ Pa,最大形变量为4.014×10^-4 mm。研究结果为全固态Yb:YAG激光器设计时选取合适参数、构建激光器系统及维护激光器正常工作提供理论依据。更多还原

【Abstract】 In order to solve the problem of thermal effect caused by laser diode end-pumped Yb: YAG composite crystal, FEA（Finite Element Analysis） thermal models with different bonding modes of peripheral cooling constant temperature and end-face heat exchange with air were established by analyzing the characteristics of the composite crystal.Based on the heat conduction theory, the temperature field, stress field and thermal deformation field of Yb: YAG composite crystals with different composite modes were numerically calculated by Poisson equation, and the temperature field and strain of Yb: YAG composite crystals with different composite modes were compared during end-pumped laser diode.The results show that: If the laser diode pump power is 50 W, the spot radius coupled to the pump surface is 400 μm, using single ended bonding and length of 0.5 mm, the Yb: YAG pure crystal size is 3 mm×3 mm×6 mm, and the doping concentration is 5.0at.%, the maximum temperature rise is 57.01 K, the maximum stress is 1.067×10⁸ Pa, and the maximum strain is 4.014×10^-4 mm.The research results provide a theoretical basis for selecting appropriate parameters, the way of constructing laser systems, and maintaining the normal operation of solid-state Yb: YAG lasers.更多还原