New physical effects on periodically grooved open dielectric waveguides

When a surface wave strikes a structural discontinuity on an open dielectric waveguide at oblique incidence, instead of normal incidence as most studies have assumed, the resulting boundary value problem becomes vector, and one finds a rich variety of interesting and sometimes unexpected new physical effects. Among the new physical effects described here for periodically grooved open dielectric waveguides, of importance for integrated optics and for millimeter waves, are the following: four stop bands instead of the usual two in the Bragg reflection region, beam steering and focusing, radiation at peculiar skew angles, and surprisingly large cross‐polarization effects, none of which are present for normal incidence.