锶原子光钟中repumping光频率锁定系统的研制  

The System of the Repumping Lasers′Frequency Stabilization in Strontium Optical Clock

作　　者：任洁[1,2] 田晓[1,2] 刘辉[1,2] 常宏[1] 

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

出　　处：《量子光学学报》2013年第2期106-115,共10页Journal of Quantum Optics

基　　金：国家自然科学基金(11074252;61127901);中国科学院科研装备研制项目(YZ201115)

摘　　要：锶原子光钟里两束repumping光的频率对应锶原子三重态系跃迁(5s5p)3 P0-(5s6s)3S1和(5s5p)3 P2-(5s6s)3S1,由于其跃迁基态处于亚稳态,所以较难利用原子的跃迁线作为参考对这两台激光器进行锁频。本文介绍一种基于腔传递的数字伺服系统实现这两台半导体激光器任意频率的同时锁定。通过一台F-P腔将He-Ne激光器的频率高稳定性同时传递到两台受控激光器上。LabVIEW程序自动搜索激光透射峰信号从而得到误差信号,由比例积分算法得出控制电压,并反馈回激光器。可视化界面易于操作和观察,可直接完成对激光器的锁定,并自动记录实验结果。该方法使用方便,锁定后激光器频率波动为±4MHz左右。该系统易扩展,可实现多台激光器的同时锁定。将锁定后的repumping光加入蓝MOT后,磁光阱内俘获的原子荧光强度增大了12倍,寿命提高了13倍,对于锶原子光钟一级冷却的研制有重要的应用价值。The two repumping lasers in Sr Optical Clock corresponding to the transitions of （5s5p）3 P0-（5s6s）3S1 and （5s5p）3 P2-（5s6s）3S1, which the lower state is metastable, are difficult to be locked through the atomic transition line. In this paper, we introduce a digital servo system which can lock the two lasers simultaneously in any frequency value by an F-P cavity, transferring the stability of He-Ne laser to the two repumping lasers. LabVIEW program automatically searches the lasersr transmission peaks of F-P cavity and gets the error signal, then feeds back the negative feedback voltage, calculating by the PI algorithm, to the lasers. Also, this program, with a visual interface and the merits of easy operating, can lock the laser directly and record the data automatically. The frequency deviations of the locked lasers＇ are about ± MHz. The system＇s expansibility allows more lasers to be locked simultaneously.

关 键 词：半导体激光器 数字伺服 腔传递稳频 

分 类 号：O431[机械工程—光学工程]