长波红外CdSe光参量振荡器  

Long-Wave Infrared CdSe Optical Parametric Oscillator

作　　者：魏磊 李宝[4] 陈国 方聪[4] 韩隆 苑利钢[4] 吴德成[1] 倪友保 王英俭 Wei Lei;Li Bao;Chen Guo;Fang Cong;Han Long;Yuan Ligang;Wu Decheng;Ni Youbao;Wang Yingjian(Key Laboratory of Atmospheric Optics,Anhui Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Hefei,Anhiii 230031,China;Science Island Branch,Graduate School,University of Science and Technology of China,Hefei,Anhui 230026,China;Anhui Provincial Key Laboratory of Photonic Devices and Material,Hefei,Anhui 230031,China;Key Laboratory of Science and Technology on Solid-State Laser,North China Research Institute of Electro-Optics,Beijing 100015,China)

机构地区：[1]中国科学院安徽光学精密机械研究所中国科学院大气光学重点实验室,安徽合肥230031 [2]中国科学技术大学研究生院科学岛分院,安徽合肥230026 [3]安徽省光子器件与材料重点实验室,安徽合肥230031 [4]华北光电技术研究所固体激光技术重点实验室,北京100015

出　　处：《中国激光》2021年第24期32-39,共8页Chinese Journal of Lasers

基　　金：中国科学院大气光学重点实验室开放课题基金。

摘　　要：长波红外波段的激光在大气中能够低损耗传输,这就使得长波红外激光具有广泛应用的天然优势,其中长波红外激光可用作红外光电对抗光源,特别是随着长波红外探测器的发展,其对相应波段的对抗光源的需求与日俱增。为此设计并搭建波长为2.05μm Ho∶YLF激光来泵浦长波CdSe光参量振荡器的实验装置,该装置可以输出峰值波长为12.5μm的高重频长波红外激光。激光器在重复频率5 kHz情况下的平均功率最高达526 mW,Ho∶YLF激光到长波激光的光光转换效率为1.46%,斜效率为23.4%,激光单脉冲宽度为24.4 ns,单脉冲能量为0.1 mJ,单脉冲峰值功率为4.3 kW,X方向的光束质量因子为4.3,Y方向的光束质量因子为3.2。Objective An 8-15-μm long-wave infrared(IR)laser has less transmission loss in the atmosphere;therefore,it can be used for gas detection,free-space optical communications and IR electro-optic confrontation.CO_(2) and ZnGeP_(2) optical parametric oscillator(OPO)lasers have been used to output long-wave lasers,although it is difficult to output lasers with wavelengths longer than 12μm.Moreover,research on such lasers is inadequate.In this study,we design a CdSe OPO scheme and experimentally test its long-wave IR output.The results show that lasers with wavelength larger than 12μm can be obtained by using CdSe OPO,which provides a solution for obtaining lasers with longer wavelengths.Methods The scheme of the OPO-based long-wave IR laser pumped using a 2-μm laser is discussed,in which the selection of a non-linear long-wave IR crystal is included.In this scheme,the selected non-linear crystal is CdSe and the selected pumping laser source is 2.05μm Ho∶YLF laser with a maximum output power of 40 W(frequency is5kHz).The two end faces of the CdSe crystal are polished and coated with an anti-reflection film at 2,2.4-2.7and10-13μm bands,which are the key processes for reducing the optical loss and risk of damage in the crystal.The resonator of the OPO is a flat cavity,and the resonant mode is a single-resonance OPO.The Ho∶YLF laser is linearly polarised,which is helpful for CdSe OPOs to achieve a high optical-to-optical conversion efficiency.The Ho∶YLF laser pulsed using an acousto-optic Q-switch is pumped via a Tm∶YAP laser continuous wave with a 1.94-μm wavelength and 78-W maximum output power.The Q-switch and all crystals are wrapped in thin indium foils and placed in red copper heat sinks to collect the heat absorbed by them.During the experimental apparatus operation,there is water flow at 20℃in all heat sinks and a microchannel structure for the water flow is indicated.Finally,the typical parameters of the long-wave IR laser are measured,including average power wavelength laser beam quality repetiti

关 键 词：激光光学 长波红外 Ho∶YLF CDSE 光参量振荡器 

分 类 号：TN248.1[电子电信—物理电子学]