Investigating polarization conversion in a planar array of High Refractive Index all-dielectric nanospheres using the Coupled Electric and Magnetic Dipole formulation

The optical properties present in infinite planar arrays of nanoscatterers, metasurfaces, and metagratings have gained popularity in the scientific community because of their rich phenomenology, including both plasmonic and high-refractiveindex dielectric meta-atoms to yield a variety of electric and magnetic resonant responses. The coupled electric and magnetic dipole analytical formulation based on a two-dimensional depolarisation Green function is specifically used to analyse the reflection and transmission of an infinite array of periodic nanospheres for specular diffraction, although it has evidently been applied to higher diffractive orders. The poles of the said Green function were extracted by the calculation of resonances corresponding to the electric and magnetic dipoles respectively, and bound states in the continuum for varying polarizations of the electromagnetic field. This method, proved to achieve polarisation conversion would particularly be applicable to antenna setup, but in a more general sense useful for the investigation of electromagnetic properties in plasmonic, all-dielectric and hybrid metastructures.