利用解压缩磁光阱技术实现铷87原子的亚多普勒冷却  

Sub-Doppler cooling of ^(87)Rb atoms using decompressed magneto-optical trap technique

作　　者：张东方[1,2,3] 高天佑 孔令冉[1,2,3] 李凯 江开军 ZHANG Dongfang;GAO Tianyou;KONG Lingran;LI Kai;JIANG Kaijun(State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China;Center for Cold Atom Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China;Uaiversity of Chinese Academy of Scieaces, Beijiag 100049, China)

机构地区：[1]中国科学院武汉物理与数学研究所波谱与原子分子物理国家重点实验室,湖北武汉430071 [2]中国科学院武汉物理与数学研究所中国科学院冷原子物理中心,湖北武汉430071 [3]中国科学院大学,北京100049

出　　处：《量子电子学报》2018年第3期308-312,共5页Chinese Journal of Quantum Electronics

基　　金：国家自然科学基金;91336106~~

摘　　要：利用解压缩磁光阱(DCMOT)技术将铷87原子温度降低到多普勒冷却极限温度以下。在磁光阱中获得铷87原子冷原子团,通过减小磁场梯度、降低回泵光功率和增加冷却光失谐量进一步降低冷原子温度。通过研究原子自由飞行后密度随磁场梯度、回泵光功率和冷却光失谐量的变化关系,得到最优化的实验参数.测得DCMOT后原子的温度为129μK,低于铷87原子的多普勒冷却极限温度(144μK)。将低温冷原子直接装载到磁阱中,装载效率为25%。Temperature of ^（87）Rb atoms can be cooled below Doppler cooling limit by using the decompressed magneto-optical trap（DCMOT） technique. Cold atoms of 87 Rb are trapped in magneto-optical trap（MOT）,and the temperature of cold atoms is further lowered by decreasing the magnetic field gradient and repumping light power, increasing the detuning of cooling light. The optimal experimental parameters are obtained by investigating the relationship between atomic density after free flight and the magnetic field gradient, power of repumping light and detuning of cooling light. The atom temperature measured after DCMOT is 129 μK,which is lower than Doppler cooling limit temperature of ^（87）Rb atom（144 μK）. The low temperature cold atoms are loaded directly into the magnetic trap with a loading efficiency of 25%.

关 键 词：量子光学 磁光阱 多普勒冷却极限 解压缩磁光阱 偏振梯度冷却 

分 类 号：O431.2[机械工程—光学工程]