激光二极管抽运氦气冷却钕玻璃叠片激光放大器热致波前畸变和应力双折射的数值模拟和实验研究  

Theoretical and experimental investigations on wavefront distortion and thermal-stress induced birefringence in a laser diode pumped helium gas-cooled multislab Nd:glass laser amplifier

作　　者：黄文发[1] 李学春[1] 王江峰[1] 卢兴华[1] 张玉奇[1] 范薇[1] 林尊琪[1] 

机构地区：[1]中国科学院上海光学精密机械研究所,高功率激光物理联合实验室,上海201800

出　　处：《物理学报》2015年第8期318-326,共9页Acta Physica Sinica

摘　　要：热效应仍是限制激光放大器向高功率、高光束质量进一步发展的瓶颈问题,高效的热管理是抑制热效应的重要技术途径.研究了基于激光二极管抽运氦气冷却的钕玻璃叠片激光放大器的热效应.利用有限元数值模拟的方法,分析了钕玻璃的温度、应力应变和应力双折射分布,并计算了热致波前畸变和退偏损耗,与实验结果符合得较好,在热沉积为0.7 W/cm3的条件下,6片钕玻璃总的热致波前畸变为6.77λ,最大退偏量大于90%.Thermal effect is still the most serious problem： it restricts the high power and high beam quality of solid laser to be further enhanced. The efficient thermal management is an important approach to suppress the thermal effect. In this paper, the thermal effect in a gas-cooled laser diode pumped multislab Nd：glass amplifier operating at a repetition rate is investigated in detail both theoretically and experimentally. The three-dimensional distributions of temperature, stress, strain, and birefringence are calculated by a finite element analysis. Based on these data, the thermally induced wavefront distortions and depolarization losses are determined with considering six slabs and one laser head. It is revealed that the theoretical data are in good agreement with the experimental results： the total wavefront distortion is 6.77A and a depolarization loss of more than 90% accumulates over six slabs when the heat deposition is 0.7 W/cm^3.

关 键 词：激光二极管抽运 热效应 氦气冷却 钕玻璃激光放大器 

分 类 号：TN722[电子电信—电路与系统]