Scalar Potential Formulation in Spherical Coordinates

A scalar potential formulation for an anisotropic gyrotropic medium containing sources is developed. The formulation results in two forced coupled scalar Helmholtz-like equations. The results simplify to well-known relations upon specialization to an isotropic medium. A radial magnetically-biased ferrite is proposed for possible application manifesting non-reciprocal behavior for controlling electromagnetic radiation and scattering.