Leakage effect due to polarization coupling in dielectric waveguides

We present here a general approach to the three-dimensional dielectric waveguides that support only mixed modes. By the method of mode matching, the wave phenomenon at the step discontinuity is analyzed in terms of the couplings among the complete sets of modes of the two waveguides in junction; thereby, a particular attention is directed to the couplings of the constituent TM and TE modes. Specifically, the guiding characteristics of uniform dielectric strip-type waveguides and dielectric grating waveguides are presented to illustrate novel effects of the polarization couplings, such as leakage of energy and unconventional stopbands of grating waveguide. The research work was systematically carried out under the guidance and supervision of Professor Arthur A, Oliner and is reorganized in memory of him.