Scattering from an abruptly terminated asymmetrical slab waveguide

The problem of the dominant TE guided-mode scattering from an abruptly terminated asymmetrical slab waveguide is examined by both the integral equation method and the variational technique. The reflection coefficient of the guided mode, the far-field radiation pattern, and the field distribution on the terminal plane are computed. Numerical results are presented for several cases of abruptly ended waveguides, including the three-layer guide and the structure with variable profile of the refractive index.