Accurate analysis of a rib waveguide by pseudospectral modal method

For optical waveguides with high index-contrast and sharp corners, the mode matching method can be used when the interfaces are only in vertical and horizontal directions. As an efficient alternative to the classical mode matching method, the pseudospectral modal method (PSMM) for diffraction gratings has recently been reformulated as a full-vectorial waveguide mode solver. In this paper, we apply the PSMM mode solver to a classical rib waveguide benchmark problem. The results show that the PSMM can give extremely high accuracy.