A simple variational approach to optical rib waveguides

A simple method for the calculation of the mode properties of optical rib waveguides is presented. The method is based on a scalar variational principle combined with a vector perturbation analysis for the polarization correction. It is demonstrated that, with the proper trial functions, the approach can predict very accurately the dispersion characteristics with much less effort (in terms of formulation and computation) than the existing numerical techniques. The field patterns of the modes can be computed from the scalar analysis. The vector property of the mode can be taken into account by a perturbation formula. The computation is carried out on an IBM PC. The user-friendly computer program is written in Fortran