Channel polaritons

Abstract
By means of Green’s second integral identity in the plane and a parametrization of the surface profile function, the dispersion relation for surface electromagnetic waves guided by a straight channel cut into the otherwise planar surface of a solid in contact with vacuum has been determined numerically. The solid can be either a metal or a dielectric medium and is characterized by an isotropic, real, frequency-dependent dielectric function ε(ω) that is negative in some range of frequencies. The resulting propagating bound electromagnetic modes are called channel polaritons.