原子自旋惯性测量的偏振误差分析及抑制方法  

Analysis and Suppression of Polarization Error in Atomic Spin Inertial Measurement

作　　者：张伟佳 范文峰[1,2] 范时秒 全伟 Zhang Weijia;Fan Wenfeng;Fan Shimiao;Quan Wei(School of Instrumentation and Optoelectronic Engineering,Beihang University,Beijing 100191,China;Hangzhou Innovation Institute(Yuhang),Beihang University,Hangzhou 310023,Zhejiang,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]北京航空航天大学杭州创新研究院(余杭),浙江杭州310023

出　　处：《中国激光》2022年第19期33-39,共7页Chinese Journal of Lasers

基　　金：国家自然科学基金(62103026)。

摘　　要：在基于无自旋交换弛豫(SERF)的原子自旋惯性测量系统中,通过测量检测光的旋光角来实现角速率测量,检测系统的偏振误差作为直接干扰量耦合在输出信号中导致漂移,严重降低了惯性测量系统的长期稳定性。理论推导了检测系统中残余旋光角与输出信号的关系,定量分析了单位残余旋光角变化引起的SERF原子自旋惯性仪表的漂移指标变化,得到了偏振波动敏感系数。提出了一种基于偏振波动敏感系数优化的偏振误差抑制方法。调节检测激光波长,使系统工作在刻度系数最大值处,并降低原子气室温度,进行了实验验证。最后利用Allan方差对SERF原子自旋惯性测量装置的测试数据进行了漂移误差分析,零偏不稳定性由0.012(°)/h降低至0.008(°)/h,实现了偏振误差的抑制。Objective A spin-exchange relaxation-free(SERF)atomic co-magnetometer achieves angular velocity measurement by determining the probe laser's optical rotation angle.The detection system's polarization error,as a direct interference quantity,is coupled with the output signal and leads to the signal drifting,which sufficiently decreases the inertial measurement system's long-term stability.In the SERF atomic co-magnetometer detection system,the polarization error primarily originates from the non-desirable elliptical polarization component and polarization azimuth error.Most studies focus on the analysis and suppression of the non-desirable elliptical polarization component,but the polarization azimuth error caused by the residual rotation angle has not been widely researched.Thus,the signal drift caused by this polarization error needs to be resolved immediately,and the accuracy of the SERF atomic co-magnetometer needs to be improved.In this study,a polarization error suppression approach based on the optimization of polarization fluctuation sensitivity coefficient is suggested.The accuracy of the atomic co-magnetometer is enhanced by modifying the probe laser wavelength corresponding to the scale coefficient's maximum value and decreasing the atomic vapor cell's temperature.Furthermore,this approach does not add additional devices that can introduce other noises and is simpler to scale down.Methods In this study,by optimizing the polarization fluctuation sensitivity coefficient,the polarization error of the SERF atomic co-magnetometer is suppressed.First,the equation for the output signal of the SERF atomic comagnetometer under ideal conditions is modified,considering that the actual atomic spin precession detection system will introduce inevitable residual optical rotation angle error due to the imperfect manufacturing process of optical components or the changes of the ambient temperature and mechanical stress.The influence of the spurious angular velocity caused by the residual optical rotation angle on the co-

关 键 词：测量 旋光角 偏振误差 敏感系数 原子自旋惯性测量 长期稳定性 

分 类 号：O436.3[机械工程—光学工程]