Voigt Exceptional Points in an Anisotropic ZnO-Based Planar Microcavity : Square-Root Topology, Polarization Vortices, and Circularity
Voigt points represent propagation directions in anisotropic crystals along which optical modes degenerate, leading to a single circularly polarized eigenmode. They are a particular class of exceptional points. Here, we report the fabrication and characterization of a dielectric, anisotropic optical microcavity based on nonpolar ZnO that implements a non-Hermitian system and mimics the behavior of