用吸收法对铯原子磁光阱中冷原子数目的测量  

Measurement of the number of cold atoms trapped in cesium magneto-optical trap via probe absorption

作　　者：王彦华[1] 杨海菁[1] 张天才[1] 王军民[1] 

机构地区：[1]量子光学与光量子器件国家重点实验室,山西大学光电研究所,太原030006

出　　处：《物理学报》2006年第7期3403-3407,共5页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:60578018;10434080;10374062;中俄NSFC-RFBR协议项目);教育部科学技术重点项目经费(批准号:204019);教育部科技创新工程重大项目培育资金(批准号:705010);教育部长江学者和创新团队发展计划(批准号:IRT0516);山西省高校青年学术带头人科研经费资助的课题.~~

摘　　要：介绍了吸收法测量冷原子数的原理以及对铯原子气室磁光阱中俘获的冷原子数目的测量过程及结果.与通常的荧光收集法相比,在原理上与静止二能级原子同共振单模光场作用的模型更加接近,同时大大减小了测量中的误差累积,提高了测量精度.测得的冷原子数为(8±0.3)×106,同时还利用测得的阱中俘获的稳态冷原子数和磁光阱中冷原子的寿命间接获得了磁光阱的俘获率.The number of cold atoms trapped in magneto-optical trap（MOT） can be derived from probe absorption signal. After the MOT is switched off, the cold cloud freely expands in gravitational field with an initial velocity distribution. So the measurement process can be described with the interaction model between the individual stationary two-level atom and single mode resonate laser. Absorption method can largely improved the measurement precision. In this paper we introduce the physical principle of measurement and demonstrate the whole experimental procedure in detail. The number of atoms trapped in our MOT, （8±0.3）×10^6 is measured in experiment. And the number of steady-state atoms and the lifetime of atom trapped in MOT was used to deduce the capture rate of MOT.

关 键 词：激光冷却与俘获 磁光阱 冷原子数目 俘获率 

分 类 号：O562[理学—原子与分子物理]