脉冲光抽运铷原子钟的Ramsey信号特性研究  

Ramsey Signal Characteristics in a Pulsed Optically Pumped Rb Clock

作　　者：薛文祥[1,2,3] 郝强 王柯穆 王鑫[1,2] 张首刚 XUE Wen-xiang;HAO Qiang;WANG Ke-mu;WANG Xin;ZHANG Shou-gang(National Time Service Center,Chinese Academy of Sciences,Xi′an 710600,China;Key Lab of Time-frequency Standard of the Chinese Academy of Sciences,Xi′an 710600,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院国家授时中心,西安710600 [2]中国科学院时间频率基准重点实验室,西安710600 [3]中国科学院大学,北京100049

出　　处：《光子学报》2020年第5期182-188,共7页Acta Photonica Sinica

基　　金：国家自然科学基金(Nos.11706031,11606031);中国科学院西部之光(No.XAB2017B04)。

摘　　要：基于以小型化磁控管微波腔实现的脉冲光抽运铷原子钟,研究了自由演化时间对Ramsey信号特性的影响,讨论了横向弛豫时间对钟信号对比度的影响.该原子钟的自由演化时间为3ms时,Ramsey信号中心条纹的对比度为52%,散弹噪声极限优于1.7×10-14(τ=1s).利用Ramsey信号的对比度和吸收泡内的光密度,计算得到了原子钟内铷吸收泡的纵向和横向弛豫时间分别为1.95ms和2.45ms.本文研究为进一步提高脉冲光抽运铷原子钟的性能提供了重要依据.The influence of free evolution time on the Ramsey signal characteristics of a pulsed optically pumped Rb clock based on a compact magnetron microwave cavity was reported,and in addition,the effect of coherence relaxation time on the contrast of clock signal was discussed.When the optimal free evolution time of the atomic clock is about 3 ms,the Ramsey central fringe contrast is as high as 52%and the shot-noise-limit is better than 1.7×10-14(τ=1 s).According to the contrast of the Ramsey signal and the optical density in the vapor cell,both population and coherence relaxation times of Rb vapor cell in the atomic clock are 1.95 ms and 2.45 ms,respectively.The experiment provides a useful basis for improving the performance of the pulsed optically pumped Rb clock.

关 键 词：原子钟 Ramsey信号 自由演化时间 对比度 弛豫时间 

分 类 号：TM935.115[电气工程—电力电子与电力传动]