Empirical relations for the propagation characteristics of diffused channel waveguides

Abstract

Empirical relations for the propagation constant and the field profile parameters of integrated optical diffused channel waveguides have been developed. The field profile used is the evanescent secant-hyperbolic field, which has been shown earlier to be a very good approximation for diffused channel-waveguide modes. Least-square fitting has been used to obtain the empirical relations. The results show that the error in empirical relations for the propagation constant is within 2% for a broad range of waveguide parameters. The obtained empirical relations for the field profile and the propagation constant have been used, as an example, to calculate the coupling length of diffused channel-waveguide-based directional couplers.