A Simple and Accurate Modal Analysis of Strip- Loaded Optical Waveguides With Various Index Profiles

A simple first-order perturbation approach has been developed to study the propagation characteristics of strip-loaded diffused waveguides with various refractive index profiles. Propagation constants of the guided modes of rib waveguides and strip-loaded waveguides with exponential and Gaussian refractive index profiles are obtained and it is observed that our results are in good agreement with the results reported in the literature using variational and numerical techniques. The technique also provides analytical expressions for the modal field profile that should be useful in the design of various integrated optical devices.