水体参数对受激布里渊散射阈值及增益的影响  

Influence of water parameters on threshold value and gain coefficient of stimulated Brillouin scattering

作　　者：许锦 郭洋宁 罗宁宁[2] 李淑静[2] 史久林[2] 何兴道 Xu Jin;Guo Yang-Ning;Luo Ning-Ning;Li Shu-Jing;Shi Jiu-Lin;He Xing-Dao(School of Instrumentation and Optoelectronic Engineering,Beihang University,Beijing 100191,China;Key Laboratory of Opto-Electronic Information Science and Technology of Jiangxi Province,Nanchang Hangkong University,Nanchang 330063,China)

机构地区：[1]北京航空航天大学仪器科学与光电工程学院,北京100191 [2]南昌航空大学,江西省光电信息科学与技术重点实验室,南昌330063

出　　处：《物理学报》2021年第15期121-128,共8页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:41776111,61865013);国家重点研发计划(批准号:2018YFE0115700);国防工业技术发展计划项目(批准号:JCKY2019401D002)资助的课题.

摘　　要：受激布里渊散射在激光雷达海洋遥感领域具有广泛应用,而水体参数变化对其阈值及增益等关键特征参数影响的研究还很缺乏.本文利用分布式噪声模型及耦合波方程,理论分析了水的温度、压强和衰减系数对受激布里渊散射阈值和增益系数的影响.在理论分析基础上,设计了一种温度压强可控实验系统,采用平均衰减系数法实验测量了不同温度、压强及衰减系数下的阈值和增益系数.结果表明,受激布里渊散射阈值随压力和衰减系数的增大而增大,随温度的升高而减小,而增益系数则呈现与阈值相反的变化趋势.温度和衰减系数对阈值和增益系数的影响大于压力.研究结果对受激布里渊散射激光雷达海洋遥感探测具有重要意义.Stimulated Brillouin scattering(SBS)is a typical inelastic scattering effect generated by the interaction between intense incident laser and the acoustic wave field in medium and has always been an active research topic in nonlinear optics.The SBS can be used as a novel LIDAR technology for active optical remote sensing of temperature and sound speed structure in ocean.Although,the threshold value and gain property of SBS at normal temperature are studied,none of the threshold values and gain coefficients of SBS at different temperatures,pressures and attenuation coefficients has been investigated in detail.Further,neither the relation between threshold value and water pressure nor the relation between gain coefficient and water pressure is clear now,and little work has been reported.The theoretical and experimental studies of the influence of water parameters on the threshold value and gain coefficient of SBS are still scanty.In this paper,the effects of temperature,pressure and attenuation coefficient of water on threshold value and gain coefficient of SBS are studied theoretically and experimentally.Theoretically,the variations of threshold value and gain coefficient of SBS with temperature,pressure and attenuation coefficient are analyzed by the average attenuation coefficient method based on the distributed noise model(DNM)and coupled wave equations.The temporal waveforms of Stokes-,pump-and transmission-beam at different water parameters are obtained by using the DNM.Experimentally,a temperature-pressure controlled simulator is designed to obtain the threshold values and gain coefficients of SBS in water at different temperatures,pressures and attenuation coefficients through measuring the change of attenuation coefficient of laser pulses.The results indicate that(i)the threshold value of SBS increases with pressure increasing at the same temperature and decreases with temperature increasing at the same pressure;(ii)the threshold value is positively correlated with the attenuation coefficient at the same te

关 键 词：受激布里渊散射 阈值 增益 水体参数 

分 类 号：O437.2[机械工程—光学工程]