Measurements of Majorana transition frequency shift in caesium atomic fountain clocks  

作　　者：施俊如 王心亮 杨帆 白杨 管勇 范思晨 刘丹丹 阮军 张首刚 Jun-Ru Shi;Xin-Liang Wang;Fan Yang;Yang Bai;Yong Guan;Si-Chen Fan;Dan-Dan Liu;Jun Ruan;Shou-Gang Zhang(National Time Service Center,Chinese Academy of Sciences,Xi’an 710600,China;Key Laboratory of Time and Frequency Primary Standards,Chinese Academy of Sciences,Xi’an 710600,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]National Time Service Center,Chinese Academy of Sciences,Xi’an 710600,China [2]Key Laboratory of Time and Frequency Primary Standards,Chinese Academy of Sciences,Xi’an 710600,China [3]University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Chinese Physics B》2023年第4期42-49,共8页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant No.12173044);Research and Development Project of Scientific Research Instruments and Equipment of Chinese Academy of Sciences(Grant No.YJKYYQ20200020);Large Research Infrastructures Improvement Funds of Chinese Academy of Sciences(Grant No.DSS-WXGZ-2020-0005);Chinese Academy of Sciences for Western Young Scholars(Grant Nos.XAB2018A06,XAB2019A07,and XAB2018B16)。

摘　　要：The caesium atomic fountain clock is a primary frequency standard.During its operation,a Majorana transition frequency shift will occur once a magnetic field at some special locations along the atomic trajectory is singular.In this study,by developing a physical model,we analyzed the magnetic field requirements for atomic adiabatic transition and calculated the influence of the Majorana atomic transition on the atomic state via a quantum method.Based on the simulation results for the magnetic field in the fountain clock,we applied the Monte Carlo method to simulate the relationship between the Majorana transition frequency shift and the magnetic field at the entrance of the magnetic shielding,as well as the initial atomic population.Measurement of the Majorana transition frequency shift was realized by state-selecting asymmetrically populated atoms.The relationship between the Majorana transition frequency shift and the axial magnetic field at the entrance of the magnetic shielding was obtained.The measured results were essentially consistent with the calculated results.Thus,the magnetic field at the entrance of the magnetic shielding was configured,and the Majorana transition frequency shift of the fountain clock was calculated to be 4.57×10^(-18).

关 键 词：caesium atomic fountain clock Majorana transition frequency shift magnetic field initial atomic population 

分 类 号：TH714.14[机械工程—测试计量技术及仪器]