Enhancement of signal-to-noise ratio of ultracold polar NaCs molecular spectra by phase locking detection  

作　　者：王文浩 刘文良 武寄洲 李玉清 王晓锋 刘艳艳 马杰 肖连团 贾锁堂 

机构地区：[1]State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China [2]Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China

出　　处：《Chinese Physics B》2017年第12期227-231,共5页中国物理B（英文版）

基　　金：Project supported by the National Key Research and Development Program of China(Grant No.2017YFA0304203);the Chang Jiang Scholars and Innovative Research Team in the University of the Ministry of Education of China(Grant No.IRT13076);the National Natural Science Foundation of China(Grant Nos.91436108,61378014,61675121,61705123,and 61722507);the Fund for Shanxi“1331 Project”Key Subjects Construction,China;the Foundation for Outstanding Young Scholars of Shanxi Province,China(Grant No.201601D021001)

摘　　要：We report a method of high-sensitively detecting the weak signal in photoassociation （PA） spectra of ultracold NaCs molecules by phase sensitive-demodulated trap-loss spectra of Na atoms from a photomultiplier tube. We find that the signal-to-noise ratio （SNR） of the PA spectra is strongly dependent on the integration time and the sensitivity of the lock-in amplifier, and our results show reasonable agreement with the theoretical analyses of the SNR with the demodulation parameters. Meanwhile, we investigate the effect of the interaction time of the PA laser with the colliding Na-Cs atom pairs on the SNR of the PA spectra. The atom loss rate is dependent on both the PA-induced atom loss and the loading of the MOT. The high-sensitive detection of the excited ultracold NaCs molecules lays a solid foundation for further study of the formation and application of ultracold NaCs molecules.We report a method of high-sensitively detecting the weak signal in photoassociation （PA） spectra of ultracold NaCs molecules by phase sensitive-demodulated trap-loss spectra of Na atoms from a photomultiplier tube. We find that the signal-to-noise ratio （SNR） of the PA spectra is strongly dependent on the integration time and the sensitivity of the lock-in amplifier, and our results show reasonable agreement with the theoretical analyses of the SNR with the demodulation parameters. Meanwhile, we investigate the effect of the interaction time of the PA laser with the colliding Na-Cs atom pairs on the SNR of the PA spectra. The atom loss rate is dependent on both the PA-induced atom loss and the loading of the MOT. The high-sensitive detection of the excited ultracold NaCs molecules lays a solid foundation for further study of the formation and application of ultracold NaCs molecules.

关 键 词：ultracold NaCs molecules PHOTOASSOCIATION high-resolution spectroscopy signal-to-noise ratio 

分 类 号：O561.3[理学—原子与分子物理]