用于原子干涉仪实验的锂原子的塞曼减速与磁光囚禁

为了制备适于原子干涉仪实验的低温锂原子样品,开展了锂原子的塞曼减速及与磁光阱囚禁相关的实验研究.设计并实现了一种结构紧凑的腔体内冷式多级线圈叠加的塞曼减速器,将速度小于600 m/s的7Li原子减速到60 m/s,磁光阱装载速率为5×108/s,囚禁原子数目1×109个,原子团的最低温度约为220±30μK.研究了光学黏胶中7Li原子的寿命与囚禁光频率失谐量的关系.这些结果为进一步开展7Li原子亚多普勒冷却、光势阱蒸发冷却以及原子干涉仪实验奠定了基础.

Zeeman slowing and magneto-optically trapping of lithium atoms in atomic interferometry experiments

To prepare cold lithium atoms for atomic interferometry experiments, we have carried out experimental researches on Zeeman deceleration and magneto-optical trap (MOT) of lithium atoms. We have also designed and implemented a compact adjustable Zeeman slower with an inner water cooling chamber, to decelerate the velocity of the ⁷Li atom beam from 600 m/s down to 60 m/s, and load them into the MOT. The loading rate is 5×10⁸ /s, the total trapped atom number is 1×10⁹ , and the lowest temperature of the atom cloud is 220 ± 30 μK. Then we investigate the dependence of lifetime of ⁷Li atoms in optical molasses on the detuning of trapping laser beams. The above results lay a foundation for further sub-Doppler cooling, optical trap based on evaporative cooling, and atomic interferometry experiments.
Keywords：laser cooling and trappingZeeman slowermagneto-optical trapatom interferometer