Solving certain leaky waveguides with lossless, simply bounded, finite element modeling

The implementation of the finite-element method (FEM) is much simplified when studying lossless, bounded structures. An approach is described which can accurately estimate the solution of certain leaky waveguide designs by the perturbation of a similar, simply bounded FEM model. The method is used to model the ARROW (antiresonant reflecting optical waveguide) and achieves results well within 1% of those found from the full analytical model.>