Electromagnetic transparency of a magnetic heterostructure under the multiwave interference conditions

Features of resonant photon transmission that are due to the hybridization of gyrotropy and spatial dispersion, which are two independent mechanisms for the collapse of the Fano resonance, have been studied in a layer of an optically transparent magnetic dielectric between two identical anisotropically conducting metasurfaces, as well as in a finite one-dimensional superlattice with the same elementary period. In particular, it has been shown that the appearance of interference-type “dark” states with zero radiative width in the emission spectrum of radiative polaritons can be accompanied by the suppression of the full electromagnetic transparency of the layer, which is inherent in the two-mode model of the formation of such bound states in the continuum. The radiative polariton mode simultaneously appearing in the layer can become superradiant for a photonic crystal of the considered type, which will lead to almost total photon reflection.