Electromagnetic Scattering by a Gyrotropic-Coated Conducting Sphere Illuminated From Arbitrary Spatial Angles

This communication presents the development of a Mie-based scattering theory for a gyrotropic-coated conducting sphere such that an arbitrary incident angle can be modeled analytically from an eigen-system determined by gyrotropic permittivity and permeability tensors. The incident and scattered fields can be expanded in terms of spherical vector wave functions (SVWFs). After the unknown scattering coefficients are obtained in the general gyrotropic media, the expansion coefficients associated with the eigenvectors and scattering coefficients can be determined by matching boundary conditions at the interfaces between different media. The scattering property of a gyrotropic object relies on where the illumination comes from, and hence it is different from the isotropic cases. This analytical approach enables the modeling of scattering by a gyrotropic-coated conducting sphere under arbitrary incident angles and polarizations.