Enhanced magneto-optical intensity effect in a helicity-preserving all-dielectric metasurface at Mie resonances and the anapole state
Phys. Rev. A 114, 043509 – Published 8 October, 2026
DOI: https://doi.org/10.1103/stcb-l9dz
Abstract
Nanophotonic structures provide an efficient route to enhancing magneto-optical effects by concentrating electromagnetic fields at subwavelength scales. In this work, we propose an all-dielectric metasurface that preserves the helicity of normally incident light and experimentally demonstrate the resonant enhancement of magnetization-induced transmission modulation under circularly polarized excitation. The optical response of the structure is governed by the Mie resonances of silicon nanodiscs and by a spectral feature associated with the anapole state. In the spectral regions of the Mie resonances, the metasurface exhibits the largest enhancement relative to a bare magnetic film, with the normalized magneto-optical intensity effect increased by a factor of about 2 to 3. A strong response is also observed in the high-transmission spectral region associated with the anapole state, which is manifested as a local transmission maximum. In this regime, the normalized magneto-optical intensity effect exceeds that of the bare magnetic film by about 37%, while the metasurface transmission remains above 80%. The pronounced magneto-optical response in this spectral region is preserved over a broad range of incidence angles.
