100 Hz LiNbO_(3)声光调Q 2.79μm激光器的脉冲输出特性  

Pulse Output Characteristics of LiNbO_(3)Acousto⁃Optic Q⁃switched 2.79⁃μm Laser at 100 Hz

作　　者：姜玲玲 马圣洁 朱永斌 程庭清[1] 江海河[1,2] Jiang Lingling;Ma Shengjie;Zhu Yongbin;Cheng Tingqing;Jiang Haihe(Institute of Health and Medical Technology,Hefei Institutes of Physical Science,Chinese Academy of Sciences,Hefei 230031,Anhui,China;University of Science and Technology of China,Hefei 230026,Anhui,China)

机构地区：[1]中国科学院合肥物质科学研究院健康与医学技术研究所,安徽合肥230031 [2]中国科学技术大学,安徽合肥230026

出　　处：《中国激光》2023年第23期130-136,共7页Chinese Journal of Lasers

基　　金：国家重点研发计划(2018YFB0407204)。

摘　　要：对闪光灯泵浦的2.79μm Er,Cr∶YSGG激光器在高重复频率下的声光调Q输出特性进行了研究。当射频驱动功率为30 W时,LiNbO_(3)声光开关实现了最大的衍射效率和稳定的调Q特性。当重复频率为100 Hz时,实验研究了不同反射率下LiNbO_(3)声光调Q Er,Cr∶YSGG激光器的输出特性,采用平凸谐振腔补偿增益介质中的热透镜效应,明显改善了Er,Cr∶YSGG激光器的调Q输出性能,在平凸腔中能够得到最大的脉冲能量和最短的脉冲宽度。与平平腔相比,平凸腔将激光器的输出能量提高了1.5倍。当重复频率为100 Hz时,激光系统输出的脉冲能量的最大值为4.36 mJ,脉冲宽度的最小值为76.8 ns。Objective Currently,nanosecond pulsed 3μm lasers are of interest for many scientific research and practical applications.For midinfrared optical parametric oscillators(OPOs),pumping sources with longer wavelengths are desirable to reduce the quantum loss in the parametric conversion.Moreover,pumping sources with short pulse duration and high peak power can improve the conversion efficiency to the mid-infrared wavelength(3‒12μm range)and obtain greater output power or energy.Another important application of nanosecond pulsed 3μm lasers is related to the distinctive features of water and hydroxyapatite,i.e.,extremely high absorption in the vicinity of the 3μm wavelength range.Therefore,pulsed lasers in this wavelength range are widely employed for medical ablation surgery,particularly for dental and orthopedic applications.Further,lasers with high repetition rate can improve the ablation efficiency of hard tissue and speed up the treatment process.If the laser pulse duration is less than the thermal diffusion time,unnecessary thermal damage to the surrounding healthy tissue can be reduced.Therefore,it is a common endeavor to achieve a stable 3μm laser output with a high peak power and short pulse duration at a high repetition rate.Bulk LiNbO_(3)crystals have excellent acousto-optical(AO)properties and can be used as an ideal AO medium,exhibiting higher transmission in the 3μm wavelength range,lower acoustic attenuation coefficient(1 dB/cm@1 GHz),and higher damage threshold(>200 MW/cm2).More than 30 years ago,scientists attempted to use LiNbO_(3)crystals to create an AO Q switch,but it failed to work at 3μm wavelength.Recently,we innovated and developed a LiNbO_(3)-based AO Q switch,and its effectiveness was verified in our previous study.In this work,the output characteristics of a LiNbO_(3)AO Q switch at a high repetition rate are investigated in an Er,Cr∶YSGG laser.Hence,the output characteristics of an AO Q-switched Er,Cr∶YSGG laser pumped by a flash lamp at a high repetition rate are studied.The th

关 键 词：激光器 固体激光器 Er Cr∶YSGG LiNbO_(3)声光调Q 平凸谐振腔 

分 类 号：TN248.1[电子电信—物理电子学]