Finite element analysis of the ARROW leaky optical waveguide

The implementation of the finite element method is much simplified when studying lossless, bounded structures. An approach is described which estimates the solution of a leaky waveguide, the rib ARROW (antiresonant reflecting optical waveguide), by a perturbation of the solution of a similar, but bounded, FEM model. By focusing on designs with low rib heights, the quasi-TE characteristic of the hybrid mode of interest is exploited, simplifying the solution. It is shown that lower rib heights result in lower leakage attenuation. This approach is shown to compare favorably to the effective index method.>