宽带高增益钕玻璃放大器在惯性约束聚变(ICF)激光驱动器研究中具有重要意义。对影响激光二极管阵列(LDA)抽运钕玻璃棒状放大器增益的各因素进行分析, 确立了放大器的优化参量。建立了模拟环形LDA侧面抽运钕玻璃棒状放大器功率沉积过程的光线追迹模型, 并开发相关程序。在模拟计算基础上, 分别优化了LDA直接耦合抽运和LDA准直耦合抽运这两种构型的放大器参数。最后引入了指向误差分析, 比较了这两种耦合方式的优劣, 最终将放大器定为直接耦合抽运方式。按照优化后的结构加工了8.1 kW激光二极管抽运的2 mm钕玻璃放大器, 放大器的荧光分布均匀, 当抽运功率为7.7 kW时, 得到了40倍的小信号增益, 且放大器后增加偏振片时所测增益稳定性较好。

Nd3+-doped phosphate glass amplifier with high gain and broad band is important in inertial confinement fusion (ICF) laser driver research. After analyzing all the factors which determine gain of a laser diode array (LDA) pumped Nd glass rod amplifier, the optimum parameters are presented. The ray-tracing model is set up to simulate the deposition process of LDA side-pumped Nd glass rod amplifier, and the relative program is developed. Based on the simulation, the structures of amplifiers without and with micro-lens are optimized. From the error analysis of LDA pointing, it is found out that the amplifier without micro-lens is more preferable. A rod amplifier with 2 mm Nd glass and 8.1 kW pumping power is manufactured. The fluorescence distribution of the amplifier is uniform. As pumping power is 7.7 kW, the amplifier gain is 40. When a polarizer is added behind the amplifier, gain of the amplifier is very stable.