大芯层尺寸Yb:YAG晶体波导的设计  

Design of Large-Core Yb:YAG Crystal Waveguide

作　　者：程德江 胡星[1] 惠勇凌[1] 姜梦华[1] 雷訇[1] 李强[1] Cheng Dejiang;Hu Xing;Hui Yongling;Jiang Menghua;Lei Hong;Li Qiang(Institute of Laser Engineering,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学激光工程研究院

出　　处：《激光与光电子学进展》2019年第23期176-182,共7页Laser & Optoelectronics Progress

基　　金：国家自然科学基金(61378023);北京市自然科学资助项目(4174085);北京市自然科学基金(KZ201610005006)

摘　　要：采用无胶键合(AFB)技术制备的晶体波导具有良好的模式限制作用。在考虑模式竞争的情况下,对晶体波导的单横模条件进行计算,得出在芯层材料为原子数分数为1%的Yb∶YAG,内包层材料为原子数分数为0.5%的Er∶YAG中,芯层和内包层的单横模厚度范围。计算结果表明芯层厚度上限可以增大为传统计算结果的1.79倍,为同时实现大模场面积和单横模输出提供了理论支持。通过实验制备出芯层尺寸为320μm×400μm的大芯层尺寸Yb∶YAG晶体波导,并将该晶体波导作为增益介质搭建了晶体波导激光器,得到了1030nm激光输出,其最高输出功率为26W,斜率效率为31.5%,此时光束质量因子为M_x^2=1.22,M_y^2=1.05。实验结果证明该晶体波导能够实现近衍射极限输出,引入模式竞争来实现大芯层尺寸晶体波导单横模输出的设计方法可靠。Crystal waveguides prepared by adhesive-free bonding techniques demonstrate strong mode-limiting effects.In this paper,the crystal waveguide′s single transverse mode condition is calculated in the context of mode competition.The single transverse mode thickness range of the core and inner cladding is obtained when the core material is Yb:YAG with atomic number fraction of 1% and the inner cladding material is Er:YAG with atomic number fraction of 0.5%.Results from these calculations show that the maximum core thickness can be increased to approximately 1.79 times of the traditional calculation results obtained without mode competition.This finding provides theoretical support for the possibility of simultaneous large-mode area and single transverse mode output.A large-core Yb…YAG crystal waveguide with a core size of 320μm×400μm is prepared in the experiment.The crystal waveguide is used as a gain medium to build a crystal waveguide laser that could output a 1030-nm laser.The laser′s maximum output power is 26 W,with a slope efficiency of 31.5%and beam quality factors of M_x^2=1.22 and M_y^2=1.05.These experimental results demonstrate that the crystal waveguide can achieve an output that approaches the diffraction limit.The introduction of mode competition is a reliable design method for achieving single transverse mode output in a large-core crystal waveguide.

关 键 词：激光器 固体激光器 晶体波导 模式竞争 单横模 

分 类 号：TN248.1[电子电信—物理电子学]