Scattering by a three-dimensional object composed of the simplest Lorentz-nonreciprocal medium.

Abstract

The simplest Lorentz-nonreciprocal medium has the constitutive relations (D=ϵ0E-Γ×H and B=μ0H+Γ×E). Scattering by a three-dimensional object composed of this medium was investigated using the extended boundary condition method. Scattering by this object in free space must be attributed to nonzero Γ=|Γ|. The differential scattering efficiency is immune to the transformation of the incident toroidal electric field phasor into a poloidal electric field phasor, or vice versa, and a consequence of this source invariance is the polarization-state invariance of the differential scattering efficiency when the irradiating field is a plane wave. Both the total scattering and forward-scattering efficiencies of an ellipsoid composed of the simplest Lorentz-nonreciprocal medium are maximum when the plane wave is incident in a direction coparallel (but not antiparallel) to Γ, and the backscattering efficiency is minimum when Γ is parallel to the incidence direction. The total scattering and forward-scattering efficiencies are maximum when the incidence direction is parallel to the largest semi-axis of the ellipsoid if the incidence direction is coparallel (but not antiparallel) to Γ. Lorentz nonreciprocity in an object is thus intimately connected to the shape of that object in affecting the scattered field.