Surface Electromagnetic Waves on the Interfaces of Gradient Dielectric Media: Visible Spectral Range

Abstract

This paper is devoted to a peculiar branch of surface electromagnetic waves, belonging to the visible spectral range. Contrary to the well known surface waves, supported by the sharp boundary of solid plasma in metals and semiconductors, the waves discussed here are shown a gradient interface of non‐conducting gradient dielectric without free carriers. The subsurface layer of this dielectric is characterized by the gradual decrease of dielectric permittivity in the direction , normal to the boundary = 0, saturated in the depth of medium. Unlike the traditional condition , the field's localization near the interface of the dielectric is determined by another condition: grad , meanwhile . Spectra of surface modes are determined by the non‐local dispersion, stipulated by the spatial distribution . The spatial structure of surface wave fields is examined by means of two different exactly solvable models . The broadband and wide band spectral ranges of visible surface waves illustrating the sensitivity of their spectra to the fine details of distribution , presented by these models, are considered.