光致规范场下的冷原子及自旋量子霍尔效应

Light-induced spin Hall effects in cold atoms

讨论了冷原子与激光场的互作用系统，对于碱金属原子例如^6Li与激光场互作用系统，通过恰当的光场参数配置，构造出具二重兼并的能量本征态，可以分别定义两个简并态为自旋向上及自旋向下态，类似于自旋二分量体系。进一步研究发现，不同自旋态将感受到自旋相关的光致规范场。当原子在设定的空间分布激光场中运动时，其所感受到的有效自旋相关规范场将导致自旋霍尔效应，并产生可观测的自旋霍尔流。

The dynamics of cold atoms interacting with external laser fields is investigated. For multilevel atoms interacting with external laser fields, e.g.,^6Li, two-fold degenerate dressed states are obtained under appropriate parameters configuration, which may be defined as spin-up and spin-down in analogy with the ,spin-1/2 charged system. Further analysis shows that different spin states will feel spin-dependent gauge fields. When the cold atoms move in spatially varying laser fields, the effective spin-dependent gauge potential will lead to spin Hail effects as well as observable spin Hall currents.