Optical polarization singularities in near fields from the perspective of the duality between singular optics and non-Hermitian physics

报告题目：Optical polarization singularities in near fields from the perspective of the duality between singular optics and non-Hermitian physics

报  告  人：张若洋（香港科技大学）

时间地点：2023年1月9日（周一）14:00-17:00    

腾讯会议：847-602-962

邀  请  人：韩德专

报告摘要：

He will introduce their recent discovery that the topology of structures fundamentally dictates the topological properties of optical fields and offers a new dimension to exploit for optical functionalities that are irrelevant to specific material constituents or structural geometries. They establish two index theorems for the polarizations singularites (PSs) on the metal surfaces which reveal that the nontrivial topology of metal structures ensures the birth of polarization PSs in the near fields. By mapping the PSs to non-Hermitian degenerate points and using homotopy theory, they extract the core invariant that governs the topological classification of the PSs and the conservation law that regulates their spatial evolutions. Their results bridge singular optics, topological photonics, and non-Hermitian physics, with potential applications in chiral sensing, chiral quantum optics, and beyond photonics in other wave systems.

报告人简介：

张若洋，2016年于南开大学陈省身数学研究所理论物理研究室获得博士学位。现为香港科技大学研究助理教授。他的研究领域涵盖拓扑光子学，非厄米物理以及电动力学的几何基础。目前已在Nature, Nature Physics, Nature Communications, Physical Review Letters等国际知名期刊发表SCI论文40余篇。