基于激光双边带抑制的冷原子干涉相移优化与控制  

Optimization and control of cold atom interference phase shift based on laser double-sideband suppression

作　　者：叶留贤 许云鹏 王巧薇 程冰 吴彬[1] 王河林[1] 林强[1] Ye Liu-Xian;Xu Yun-Peng;Wang Qiao-Wei;Cheng Bing;Wu Bin;Wang He-Lin;Lin Qiang(Zhejiang Provincial Key Laboratory of Quantum Precision Measurement,College of Science,Zhejiang University of Technology,Hangzhou 310023,China)

机构地区：[1]浙江工业大学理学院,浙江省量子精密测量重点实验室,杭州310023

出　　处：《物理学报》2023年第2期82-92,共11页Acta Physica Sinica

基　　金：国家重点研发计划(批准号:2017YFC0601602)资助的课题.

摘　　要：采用电光调制技术产生冷原子干涉所需要的拉曼光,虽然可以使激光系统更加紧凑和稳定,但其产生的残余边带会引入附加干涉相移,从而影响冷原子干涉测量精度.为了降低激光调制边带对冷原子干涉相移的影响,构建了一种用于冷原子干涉的双边带抑制激光系统.基于该系统,详细分析了激光双边带的产生原理和双边带抑制效果;研究了当残余边带存在时,拉曼反射镜的初始位置、相邻拉曼脉冲的间隔时间、调制深度和原子团初速度等一系列参数与冷原子干涉相移之间的关系,并优化相关参数,降低了残余边带对冷原子干涉相移的影响.当拉曼反射镜与冷原子团之间的距离为105 mm,相邻拉曼脉冲的间隔时间为82 ms时,相移可以优化到0.7 mrad.该研究结果为减小拉曼边带效应对冷原子干涉相移的影响提供了一个思路,相应的激光系统可用于其他惯性传感器,如原子重力仪或原子重力梯度仪等.Using the electro-optical modulation method to generate Raman beams for cold atom interference is one of the better methods for constructing a more compact and robust laser system.But this way will generate some residual sidebands resulting in the additional interference phase shift,which can affect the measurement accuracy of cold atom interferometer.In order to weaken the effect of laser modulation sidebands on the phase shift of cold atom interference,a double-sideband suppressed-carrier modulation laser system for cold atom interference is constructed.Based on the designed laser system,the principle of double-sideband generation and suppression is analyzed in detail,and some residual sidebands are adjusted and controlled.Moreover,some important optical parameters that affect the phase shift of cold atomic interference,such as the initial distance between the Raman retro-reflection mirror and the atomic cloud,the interrogation time between two adjacent Raman pulses,the laser modulation depth and the initial velocity of the atomic cloud,are discussed and optimized.By optimizing these relevant parameters,the influence of residual modulation sidebands on the phase shift of cold atomic interference is weakened drastically.The research results indicate,making use of the method of double-sideband suppression,the phase shift of cold atomic interference can be optimized to 0.7 mrad when the initial distance between the Raman retro-reflection mirror and the atomic cloud is 105 mm,and the interrogation time between two adjacent Raman pulses is 82 ms.More importantly,this work can provide a method for weakening the influence of Raman sideband effect on the phase shift of cold atom interferometer,and the corresponding laser system can be applied to other inertial sensors such as atomic gravimeter or atomic gravity gradiometer.

关 键 词：原子干涉 边带抑制 IQ调制 相移 

分 类 号：O562[理学—原子与分子物理] TN24[理学—物理]