LDA侧面Zigzag泵浦多边形薄片激光放大器模拟与实验研究

Simulation and experimental study of LDA Zigzag side-pumped polygonal thin-disk laser amplifier

介绍了一种激光二极管叠阵(LDA)侧面Zigzag泵浦多边形薄片激光放大器构型,采用三维光线追迹方法进行了详细的模拟仿真,优化设计了此放大器系统的泵浦耦合结构,主要研究了多边形增益介质的掺杂离子浓度与侧面切角对介质内部泵浦光分布的影响。在晶体厚度1.5 mm、端面口径16 mm的条件下,侧面切角在35°~65°,Nd^(3+)掺杂浓度为0.20 at.%~0.30 at.%时,模拟仿真中Nd:YAG多边形薄片对泵浦光的吸收分布较均匀,泵浦光分布均匀性均优于0.1,同时在实验中得到了平顶的荧光分布和增益分布。介质内储能的均匀平顶分布有利于实现高功率高光束质量的激光输出,为侧面Zigzag泵浦多边形薄片激光器系统的设计与进一步实验提供了重要参考。

A laser diode array(LDA)zigzag side-pumped polygonal thin-disk laser amplifier configuration was introduced.The three-dimensional ray tracing method was used for the detailed simulation,and the pump coupling structure of this amplifier system was optimized and designed.The effects of the doping ion concentration of polygonal gain medium and the side cutting angle on the pump light distribution in medium were mainly studied.Under the condition that the crystal thickness is 1.5 mm and the end face diameter is 16 mm,when the side cutting angle in the range of 35°to 65°and the Nd3+doping concentration in the range of 0.20 at.%to 0.30 at.%,the Nd:YAG polygonal thin-disk has relatively uniform distribution of the pump light in simulation,and the pump light distribution uniformity is better than 0.1.The flat-topped distribution of fluorescence and gain distribution are also obtained in the experiment.The uniform flat-topped distribution of energy storage in medium is conducive to the realization of high power and high beam quality laser output,which provides many important references for the design and experiments of the zigzag side-pumped polygonal thin-disk laser system.