高光束质量窄纳秒脉宽Nd∶YVO_(4)板条脉冲串激光器  

Nd∶YVO_(4) Slab Burst-mode Laser with High Beam Quality and Short Nanosecond Pulse Width

作　　者：宋越 王志敏[1,2] 杨熙航 薄勇[1,2] 张丰丰 张艺轩 周子涵 赵文成 林延勇[1,2] 付莉 彭钦军[1,2] Song Yue;Wang Zhimin;Yang Xihang;Bo Yong;Zhang Fengfeng;Zhang Yixuan;Zhou Zihan;Zhao Wencheng;Lin Yanyong;Fu Li;Peng Qinjun(Key Laboratory of Solid-State Laser,Technical Institute of Physics and Chemistry,Chinese Academy of Sciences,Beijing 100190,China;Key Laboratory of Functional Crystal and Laser Technology,Technical Institute of Physics and Chemistry,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院理化技术研究所中国科学院固体激光重点实验室,北京100190 [2]中国科学院理化技术研究所中国科学院功能晶体与激光技术重点实验室,北京100190 [3]中国科学院大学,北京100049

出　　处：《中国激光》2023年第7期161-167,共7页Chinese Journal of Lasers

基　　金：国家自然科学基金(61535013,11504389);国家重点科学仪器装备发展项目(2012YQ120048);中国科学院科研仪器设备研制项目(GJJSTD20200007)。

摘　　要：提出了一种高光束质量、窄纳秒脉宽、高重复频率脉冲串输出的电光调Q激光器。通过优化键合Nd∶YVO_(4)板条晶体掺杂区域的纵横比,结合腔模的最佳设计,限制腔内的高阶模式振荡,获得了两方向相近的高光束质量激光输出。利用激光二极管侧面泵浦键合的Nd∶YVO_(4)板条晶体,采用电光调Q技术,研究了不同重复频率下1064 nm脉冲串激光的输出特性。在输出镜最佳透过率为40%、子脉冲调Q重复频率为80 kHz的条件下,获得了平均输出功率为5.03 W、子脉冲能量为0.50 mJ、子脉冲宽度为5.9 ns的脉冲串激光输出。在谐振腔内加入小孔光阑,获得了平均输出功率为2.56 W、子脉冲能量为0.26 mJ、子脉冲宽度为7.2 ns的脉冲串激光输出,对应的x和y方向的光束质量因子分别为1.42和1.49。Objective Laser-diode-pumped compact all-solid-state lasers with a high repetition frequency,short pulse width,and high beam quality have a wide application range in laser ranging,LIDAR detection,laser communication,and industrial processing.However,the thermal effect of solid-state lasers under high-power pumping is a crucial factor limiting the combination of the high single-pulse energy,high repetition frequency,and high beam quality characteristics of pulsed lasers.The burst-mode laser technology produces laser pulses in an intermittent mode,which alleviates the thermal effect of the continuous output of pulsed lasers to a certain extent.Common rod solid-state lasers are often end-pumped,which inevitably causes uneven heat distribution in the crystal.The slab laser reduces the temperature difference of the crystal by increasing the cooling area of the gain medium and makes the laser propagate along the zig-zag shape in the direction of the temperature gradient,which can reduce the thermal effect on the laser output to a certain extent.However,owing to the asymmetric shape of the slab gain medium,the output laser pulse is often elliptical or elongated in cross-section,resulting in a large difference in the beam quality in the x and y directions.In this study,beginning with the structure of the slab gain medium,we optimize the design of the gain medium size and aspect ratio and limit the range of the crystal doping region to reduce the thermal effect and optimize the laser spot.We hope that this method,which improves the beam quality of burst-mode lasers by optimizing the crystal structure of slabs,can also promote the development of high-energy,higher-repetition-frequency,and high-beam-quality burst-mode lasers.Methods In this study,Nd∶YVO_4 crystals with large stimulated emission cross-sections and short upper-energy-level lifetimes are side-pumped by an laser diode(LD),and both sides of the doped region are bonded with non-doped YVO_4 crystals to increase the heat dissipation area and constrain the pumping

关 键 词：激光器 电光调Q 脉冲串 高光束质量 窄脉宽 

分 类 号：TN248.1[电子电信—物理电子学]