Surface electromagnetic waves in bianisotropic superlattices and homogeneous media

Abstract

This paper analyzes the existence of surface electromagnetic waves (SEWs) at the interface of bianisotropic bicrystals which are formed of half-infinite periodic superlattices or of homogeneous bianisotropic media. In either case we assume no absorption. Properties of the impedance matrices characterizing such bianisotropic media are established. On this basis, a series of statements is proved on the maximum total number of SEWs in two bicrystals composed of two superlattices or homogeneous media in such a way that the upper (lower) half of one bicrystal complements the lower (upper) part of the other to an infinite periodic superlattice or homogeneous media, respectively. It is shown that in superlattices the maximum number of SEWs at a fixed tangential wave number equals two in the lowest forbidden band (this band begins from zero frequency) and four in any upper forbidden band. It is also proved that at most two SEWs emerge in homogeneous bianisotropic media.