Self-filtering ring optical waveguides

An analysis is made of the characteristics of three types of ring waveguide consisting of a dielectric core, an optically densest intermediate cladding, and an additional outer cladding. The use of a material with enhanced dielectric losses for the central part of the core results in higher-order filtering and the attainment of conditions approaching the single-mode regime. Such waveguides have large transverse dimensions and good dispersion properties.