A guided mode in the range of the radiation modes for a rib waveguide

Abstract : The stratified cladding of integrated optical waveguides is dispersive, which induces quite original phenomena. We present an example of a dielectric waveguide for which there exists a guided mode which propagates faster than some waves in the stratified cladding. Such a guide presents a specific symmetry and the key point is a separate study of the symmetrical and antisymmetrical modes.