^(6)Li冷原子干涉仪的实现及反冲频率精密测量  

Realization of the^(6)Li Cold Atom Interferometer and Precise Measurement of Recoil Frequency

作　　者：芮扬 张亮[1] 段春泱 刘鹏悦 余石川 武跃龙 武海斌[1,2] Rui Yang;Zhang Liang;Duan Chunyang;Liu Pengyue;Yu Shichuan;Wu Yuelong;Wu Haibin(State Key Laboratory of Precision Spectroscopy,East China Normal University,Shanghai 200241,China;Institute of Quantum Science and Precision Measurement,East China Normal University,Shanghai 200241,China)

机构地区：[1]华东师范大学精密光谱科学与技术国家重点实验室,上海200241 [2]华东师范大学量子科学与精密测量研究院,上海200241

出　　处：《激光与光电子学进展》2023年第11期248-255,共8页Laser & Optoelectronics Progress

基　　金：国家重点研发计划(2022YFA1404202);国家自然科学基金(11925401,11734008,11374101,12074125);上海市科技重大项目(2019SZZDZX01)。

摘　　要：实现了具有最轻质量碱金属^(6)Li的冷原子干涉仪,并通过精确测量其反冲频率初步获得精细结构常数。为了克服^(6)Li原子的总角动量为半整数所导致的对磁场敏感的困难,提出一种磁不敏感Raman跃迁,实现了垂直Raman光的共轭Ramsey Bordé型原子干涉仪,其相干时间超过2.3 ms。通过几何关系用四组干涉仪消除Raman光束之间角度带来的误差。测量得到的反冲频率ωr为2π×73672.789(36)Hz,精细结构常数为1/137.035976(33),是迄今为止基于冷原子干涉仪对^(6)Li反冲频率的最精确测量。^(6)Li冷原子干涉仪的实现不仅丰富了原子干涉仪的元素,而且由于其反冲频率大的特点,在精密测量领域具有极大的潜力。We report a cold atom interferometer based on the lightest alkali metal^(6)Li and measure its recoil frequency precisely,measuring the fine-structure constant on a preliminary basis.To overcome the challenges associated with magnetic-field sensitivity caused by the half-integer spin of atoms,a magnetically insensitive Raman transition and a conjugated Ramsey-Bordéinterferometer involving crossed Raman beams and coherence time>2.3 ms is realized.The error in the angles between Raman beams is eliminated using four sets of interferometers developed based on geometric relationships.The measured recoil frequencyωr is 2π×73672.789(36)Hz,and the fine-structure constant is 1/137.035976(33).These values indicate the most accurate measurements for^(6)Li obtained using the reported atom interferometer.The implementation of the^(6)Li cold atom interferometer not only enriches the elements of atom interferometers,but also has great potential in the field of precision measurement due to its high recoil frequency.

关 键 词：反冲频率测量 冷原子干涉仪 精细结构常数 

分 类 号：O431.2[机械工程—光学工程]