标题： 金属腔中由电偶极子源激发的光学偏振奇点 显示英文标题

标题： Optical polarization singularities in metallic cavities excited by electric dipole sources

摘要： 光学偏振奇点（PSs）在实空间中具有丰富的拓扑性质，可以实现对光场的高度精确操控。传统研究集中在光学系统开放空间中的PSs。光学腔体内的PSs特性仍大多未被探索。通过使用全波有限元仿真，我们研究了由电偶极子源激发的金属腔体内的光学PSs。我们确定了球形和环形腔体内奇点的拓扑指数、形态和空间演化。我们揭示了空间对称性与PSs之间的关系，以及球形腔体内偏振莫比乌斯带出现的机制。此外，我们研究了连接两种具有不同拓扑结构的几何形状（即球体和环体）的PSs的拓扑转变。结果为光学腔体内光场的奇异和拓扑特性提供了见解，并可在光学传感和小粒子的光学操控中找到应用。 显示英文摘要

摘要： Optical polarization singularities (PSs) in real space carry rich topological properties and can enable highly precise manipulations of light fields. Conventional studies focus on the PSs in the open space of optical systems. The properties of PSs inside optical cavities remain largely unexplored. By using full-wave finite-element simulations, we investigate the optical PSs inside metallic cavities excited by electric dipole sources. We determine the topological indices, morphology, and spatial evolutions of the singularities inside both spherical and torus cavities. We uncover the relationship between spatial symmetries and the PSs, as well as the mechanism underlying the emergence of polarization Mobius strips in the spherical cavity. In addition, we investigate the topological transitions of the PSs connecting two geometries (i.e., sphere and torus) with distinct topologies. The results provide insight into the singular and topological properties of light fields in optical cavities and can find applications in optical sensing and optical manipulation of small particles.