Coupled mode formulation for directional couplers with longitudinal perturbation

摘要

A grating-assisted directional coupler is investigated using an improved coupled-mode formulation for multi-waveguide systems with longitudinal perturbation. This approach is capable of handling three-dimensional structures as well as a complex index of refraction and nonisotropic media. The case of two coupled channel waveguides is closely examined, and a numerical analysis is carried out for several cases of slab structures.