FINITE-DIFFERENCE METHOD FOR ANISOTROPIC PLANAR OPTICAL WAVE-GUIDES

In this article, new finite difference approaches capable of handling anisotropic dielectric material are presented. At first, a fully vecto rial description is developed. Then the semivectorial approximation is obtained by neglecting the coupling of the dominant field component w ith the hybrid part. As a spurious mode free approach, the transverse magnetic field components H-x and H-y are used for calculating the pro pagation constants and the fields. The linear eigenvalue problems are solved by a powerful multi-grid equation solver. The convergence of th e propagation constant depending on the mesh size is shown for differe nt examples. Also the vectorial and semivectorial approaches are compa red.