Theoretical and numerical analysis of propagation and scattering of eigen- and non-eigenmodes of an irregular integrated-optical waveguide

We consider theoretical and numerical methods for studying propagation and scattering of laser radiation of eigenmodes and non-eigenmodes in an irregular integrated-optical waveguide. Scattering of non-eigenmodes in an irregular integratedoptical waveguide is investigated for the first time. We present the calculated dispersion curves for TE and TM eigenmodes and TE non-eigenmodes. For the leaky TE₀ modes we plot the dependence of the complex dispersion relation and show the vertical complex profile of the field. The dependence of the scattered laser radiation field on the effective refractive index is obtained for the given parameters of the waveguide. We compare for the first time the calculated complex scattering diagram of laser radiation outside the waveguide layer in the plane, perpendicular to the plane of incidence, for the leaky and guided TE₀ modes.