Abstract
This paper reports a computationally efficient, grid-independent method for calculating the reflectivity of deep-etch distributed Bragg reflector (DBR) gratings. The method employs Gaussian beam propagation in conjunction with a Fabry-Perot model that includes the effects of multiple reflections in multiple cavities. We include both, grating pitch and number of Bragg pairs in our analysis. We obtain very good agreement with results generated by a Helmholtz equation solver.