铁共振荧光多普勒激光雷达光源的频率稳定性研究  

Frequency stability study of the laser source for iron resonance fluorescence Doppler lidar

作　　者：李乘 吴德成 刘爽 邓迁 秘国江[4] 王邦新 王珍珠 刘东 王英俭[1,3] Li Cheng;Wu Decheng;Liu Shuang;Deng Qian;Bi Guojiang;Wang Bangxin;Wang Zhenzhu;Liu Dong;Wang Yingjian(Anhui Institute of Optics and Fine Mechanics,Hefei Institutes of Physical Science,Chinese Academy of Sciences,Hefei 230031,China;University of Science and Technology of China,Hefei 230026,China;Advanced Laser Technology Laboratory of Anhui Province,Hefei 230026,China;North China Research Institute of Electro-Optics,Beijing 100015,China)

机构地区：[1]中国科学院合肥物质科学研究院安徽光学精密机械研究所,安徽合肥230031 [2]中国科学技术大学,安徽合肥230026 [3]先进激光技术安徽省实验室,安徽合肥230026 [4]华北光电技术研究所,北京100015

出　　处：《红外与激光工程》2023年第10期65-72,共8页Infrared and Laser Engineering

基　　金：国家自然科学基金项目(41875033);中国科学院国际人才计划项目(2021VEA0006);安徽省先进激光技术实验室主任基金项目(AHL2020ZR01)。

摘　　要：种子注入的372 nm稳频Nd:YAG激光器作为铁共振荧光多普勒激光雷达的激光光源,其性能将直接影响大气温度和径向风速的测量精度,属于研制难度较大但极其重要的关键技术。文中对激光光源的频率稳定性进行了仿真分析和实验研究。利用蒙特卡洛方法,仿真了振荡级输出1116 nm脉冲光的频率稳定性(均方根)应小于1 MHz;对改进型Ramp-Fire种子注入技术进行了详细介绍,并在振荡级光路中采用了该技术;通过激光拍频实验,测量得出1116 nm脉冲光在10 min内的频率稳定性的均方根为543.24 kHz,其结果满足指标要求,可将频率抖动和频率漂移引起的系统误差减少至0.51 K和0.61 m/s。文中所做工作为铁共振荧光多普勒激光雷达实现大气温度和径向风速的高精度测量提供了必要保障。Objective Temperature and wind,as important environmental parameters,characterize the state of the atmosphere.In the region of upper mesosphere and lower thermosphere(UMLT,75-115 km),due to a lack of effective tools,there is a relative lack of observation data.The resonance fluorescence lidar uses metal atoms in the UMLT region as a neutral tracer,and it is possible to measure temperature and wind by stimulating resonance fluorescence signals of the tracer.Among many in-situ and remote sensing measurement methods,the resonance fluorescence lidar,with its high spatial and temporal resolution,high accuracy and continuous observation,has become a powerful tool.Sodium resonance fluorescence lidar is widely used in the world,while iron resonance fluorescence Doppler lidar(Fe lidar)has the advantage of whole day measurement and is also an effective means to measure temperature and wind profile.The narrow-band,frequency-stabilized laser operating at 372 nm wavelength is one of core technology in the development of Fe lidar,especially for wind measurement.To yield pulsed laser with outstanding characteristic of frequency stabilization,a theoretical and experimental study of the frequency stability of laser sources are presented.Methods The technical solution for the generation of pulsed laser is to use Nd:YAG laser to generate pulsed laser at 1116 nm wavelength,and then convert to 372 nm wavelength through subsequent second and third harmonic generation.Since the performance of oscillator determines the characteristics of the entire laser system,a theoretical and experimental study of the frequency stability mainly focuses on the oscillator.Frequency stability of pulsed laser at 1116 nm wavelength from the oscillator is simulated to be less than 1 MHz(RMS)by using the Monte Carlo method(Fig.1).A detailed description for the modified Ramp-Fire method is conducted(Fig.2),and this technology is used in the optical path of the oscillator(Fig.3(a)).In the beat frequency experiments,because of the high-frequency stability of s

关 键 词：铁共振荧光多普勒激光雷达 频率稳定性 蒙特卡洛方法 种子注入技术 激光拍频 

分 类 号：O439[机械工程—光学工程]