庞加莱光自旋密度分布的研究不仅有着实际的工程应用意义, 还对认识光的本性有着重要的意义. 研究了紧聚焦的混合阶庞加莱光的自旋密度, 发现它不仅有横向分量, 还有纵向分量; 与最近的研究总纵向自旋为零的紧聚焦满庞加莱光束不同, 其纵向总自旋不等于零. 紧聚焦的混合阶庞加莱光的自旋密度具有丰富的可调控的空间斑图, 特别是纵向自旋密度可以是环形, 还可以是正多边形等. 这些特征可用于手性微粒的光力学分离和操控, 也可用于产生等效磁场操控超冷旋量原子气体动力学.
Research on spin of Poincaré beams not only has practical engineering applications, but is also important for understanding the nature of light. In this paper, we study the spin density of the tightly focused hybrid-order Poincaré beams (TFPB) and find that it has both longitudinal and transverse components. Unlike tightly focused full Poincaré beams whose longitudinal spin density is on average zero, the total longitudinal spin density of tightly focused hybrid-order Poincaré beams is not zero. The spin density of TFPB has rich controllable spatial patterns; in particular, the longitudinal spin density can be either a ring shape or a regular polygon. These features can be used to separate chiral particles or to manipulate dynamics of ultracold spinot gases.
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中国综合性科技类核心期刊(北大核心)