MODAL-ANALYSIS OF ANISOTROPIC DIFFUSED-CHANNEL WAVE-GUIDE BY A SCALARFINITE-ELEMENT METHOD

A procedure to model optical diffused-channel waveguides is presented in this work. The dielectric waveguides present anisotropic refractive indexes which are calculated from the proton concentration. The proto n concentration inside the channel is calculated by the anisotropic 2D -linear diffusion equation and converted to the refractive indexes usi ng mathematical relations obtained from experimental data, The arbitra ry refractive index profile is modeled by a. nodal expansion in the ba se functions. The TE and TM-like propagation properties (effective ind ex) and the electromagnetic fields for well-annealed proton-exchanged (APE) LiNbO3 waveguides are computed by the finite element method.