Eigenfunctional Expansion of Dyadic Green's Functions in Gyrotropic Media Using Cylindrical Vector Wave Functions

This paper presents a novel eigenfunction expansion of the electric-type dyadic Green's function for an unbounded gyrotropic medium in terms of the cylindrical vector wave functions. The unbounded Green dyadics are formulated based on the Ohm-Rayleigh method, orthogonality of the vector wave functions, and the newly formulated curl and divergence of dyadic identities. The irrotational part of the Green's function is obtained from the residual theorem. Unlike some of the published work where some assumptions are made prior to the formulation, the irrotational dyadic Green's function in this paper is formulated rigorously based on the idea given by Tai.