高稳定高光光效率的Yb∶YAG单薄片再生放大器  

Yb∶YAG Single Thin-Disk Regenerative Amplifier with High Stability and High Optical-to-Optical Efficiency

作　　者：石玉森 李祖强 潘雪[1] 肖奇 汤晓云[1] 卢兴华[1] 王江峰[1] 张攀政[1] 姜有恩[1] 范薇[1] 李学春[1] 朱健强[1] Shi Yusen;Li Zuqiang;Pan Xue;Xiao Qi;Tang Xiaoyun;Lu Xinghua;Wang Jiangfeng;Zhang Panzheng;Jiang Youen;Fan Wei;Li Xuechun;Zhu Jianqiang(Key Laboratory of High Power Laser and Physics,Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Shanghai 201800,China;Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China)

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 [2]中国科学院大学材料与光电研究中心,北京100049

出　　处：《中国激光》2024年第2期39-44,共6页Chinese Journal of Lasers

基　　金：国家自然科学基金(11604350);中国科学院战略性先导科技专项(XDA25020307,XDA25020103)。

摘　　要：薄片激光器可以实现高峰值功率、高平均功率、高光束质量的激光输出,是高重复频率皮秒泵浦源的关键技术之一。基于Yb∶YAG单薄片激光模块设计并搭建了再生放大系统,连续泵浦下获得了平均功率为40.9 W、重复频率为1 kHz、脉冲宽度为3.4 ns的激光输出,水平方向上的光束质量因子(M_(x)^(2))和竖直方向上的光束质量因子(M_(y)^(2))分别为1.12和1.10。基于腔内光束指向主动控制技术,2 h输出的平均功率稳定性峰谷(PV)值和均方根(RMS)值分别为6.42%和0.56%。在600μs脉冲泵浦情形下,光光效率达16.1%。在10 kHz重复频率下,获得了53.3 W的高平均功率的激光输出,M_(x)^(2)和M_(y)^(2)分别为1.07和1.06。Objective In recent years,thin-disk lasers have been applied in many fields such as basic scientific research,industrial production,biomedicine,and defense.Owing to the significant advantages,such as power scalability,thermal performance,and nonlinear effects,thin-disk lasers hold great promising for high average and peak power laser while maintaining excellent beam quality.Scaling of both the average and peak powers of thin-disk lasers is possible by increasing the beam cross sections,while all internal intensities and the brightness of the pump laser are kept constant.However,the width of the dynamic stability zones of resonator cavities becomes narrower,and the output performance becomes more sensitive to cavity misalignment when the mode beam cross-section in resonators increases.These issues limit the further increase of output power of the thin-disk laser.This study reports a largemode Yb∶YAG thin-disk regenerative amplifier with active compensation for cavity misalignment.Methods The thermal focal length of a thin-disk module determines the mode distribution in the resonator cavity and should be measured before designing the cavity.The thermal focal length is measured at different pump powers using a wavefront sensor based on the principle of four-wave lateral shearing interferometry.By applying the ABCD matrix theory,the optical resonator of the thindisk regenerative amplifier is designed and optimized,to ensure the operation of the fundamental mode and to enhance resistance to cavity misalignment.The optical layout of the thin-disk regenerative amplifier is shown in Fig.1.The regenerative amplifier contains a seed laser with a narrow spectral width,an optical isolator,a Faraday rotator,a Pockels cell,thin-film polarizers,a resonator cavity,and a Yb∶YAG thin-disk module with a 24-pass pumping system.The thin disk module contains a Yb∶YAG thin-disk crystal with free aperture and thickness of 9 mm and 215μm,respectively.The pump laser can deliver up to 500 W at a wavelength of 969 nm.The multipass pu

关 键 词：激光器 薄片激光器 再生放大器 脉冲泵浦 激光稳定性 

分 类 号：TN248.1[电子电信—物理电子学]