Complete analyis of a new method for obtaining the characteristics of slab optical waveguides with step index profiles from measurements of effective indices

摘要

Abstract: A new method for characterizing step index optical waveguides from experimental values of effective indices of guided modes is presented. We find the refractive index of the film by means of a linear fitting between the square of effective index and the square of the sum of mode index plus one, avoiding the use of the highest mode; further, statistical procedure has been used to evaluate the waveguide depth through the dispersion equation (without solving the transcendental equation) avoiding the use of zeroth mode. We have checked the method by using the Monte Carlo method, analyzing all possible guides with step index profile by means of normalized parameters. Furthermore, we compare the method with those presented by other authors and we find good agreement. The proposed method is easier than others and the error analysis shows its accuracy to be good.!10