Analysis of longitudinal discontinuities in dielectric slab waveguides

Publisher Website
Google Scholar
Abstract
The interaction of waves propagating in dielectric slab waveguides with longitudinal discontinuities is treated analytically. An integral-equation approach is employed to formulate the corresponding boundary-value problem. Transverse electric (TE) and transverse magnetic (TM) waves are considered in parallel. A Fourier-series-type expansion is utilized to expand the induced field inside the discontinuity region. The unknown coefficients of this expansion are determined by solving an integral equation. Scattered wave amplitudes in the forward and backward directions are computed by applying a steepest-descent integration technique. Radiation-field patterns are also obtained for the region outside the slab waveguide. Numerical results are presented for several cases. Resonance scattering, mode mixing, and several other interesting physical phenomena are examined.