Self-consistent coupled-wave theory for circular gratings on planar dielectric waveguides

Abstract

A self-consistent coupled-wave theory for circular gratings on planar dielectric waveguides is presented. A brief description of cylindrical waves in a planar waveguide is given. The formulation of the coupled-wave theory is presented. Couplings between different cylindrical waves are discussed. It is found that (1) only cylindrical waves of the same order are coupled; (2) for zeroth-cylindrical waves, pure TE-TE (or TM-TM) wave-coupling occurs; (3) for higher order waves, there are couplings between TE- and TM-waves.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>