Anisotropic layers in waveguides for mode tuning and tunable filtering - art. no. 61350R

Modes dispersion relations of multilayered anisotropic waveguides are presented and investigated for the case of nematic liquid crystal waveguide layer. The multilayered waveguide modes are investigated using the analytic 4x4 propagation matrix approach. Dispersion relations are derived for the TE and TM confined waves for variety of orientations of the dielectric ellipsoid. For the case of coupling via a shallow grating layer where guided wave resonance is excited, it is shown that for the purpose of mode determination, this analytic approach agrees very well with rigorous diffraction calculations. Dependence of the modes on the anisotropic layer parameters is investigated particularly for liquid crystal layer parameters where thin layers are important both for single mode operation, higher switching speed, reduced absorption and scattering losses. Liquid crystals response to an applied electric field usually produces nonuniform molecular director profiles that are shown to have strong effect on the guided wave.