La 2 CaB 10 O 19 晶体高效紫外激光输出研究 Highly Efficient UV Laser Output of La 2 CaB 10 O 19 Crystal 王丽荣 WANG Li-rong 1 first-author 张国春 ZHANG Guo-chun 1 冯景程 FENG Jing-cheng 1 2 白磊 BAI Lei 1 刘丽娟 LIU Li-juan 1 王晓洋 WANG Xiao-yang 1 中国科学院理化技术研究所 北京人工晶体研究与发展中心 北京,100190 中国科学院理化技术研究所 北京人工晶体研究与发展中心 北京,100190 Beijing Center for Crystal Research and Development, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences Beijing Center for Crystal Research and Development, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences 中国科学院大学, 北京 100049 中国科学院大学, 北京 100049 University of Chinese Academy of Sciences, Beijing 100049, China University of Chinese Academy of Sciences, Beijing 100049, China La 2 CaB 10 O 19 （LCB）为可通过Nd:YAG激光三倍频产生355 nm紫外激光的非线性光学晶体，其光学性能可与商用化的LiB 3 O 5 （LBO）晶体媲美，但抗潮解特性优势明显。本文对用LCB晶体实现355 nm紫外激光输出的三倍频产生过程进行了优化设计，利用走离补偿方法来提高激光输出转换效率。通过在光路中加入沿 =45方向切割、厚度为1.2 mm的方解石晶体走离补偿片，在脉冲宽度为60 ns、重复频率10 kHz的激光参数下实现355 nm输出功率由12 W提升至20 W；在脉冲宽度为25 ps、重复频率为10 Hz的激光参数下355 nm转换效率由28.3%提升至35.2%。 La 2 CaB 10 O 19 (LCB) is a nonlinear crystal which can produce 355 nm ultraviolet (UV) laser output through the third harmonic generation (THG) of Nd:YAG laser, its optical property is comparable to that of commercial LiB 3 O 5 (LBO) crystal, with an obvious advantage in its moisture resistance. 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