Abstract

One of the most powerful beam propagation methods for analyzing optical waveguide structures is bidirectional eigenmode propagation (BEP) [1], [2]. The structure to be analyzed with the method is modelled by a stack of slices, each slice being a section of a longitudinally homogeneous waveguide, with the slice faces perpendicular to the waveguide axis, as outlined in figure 1. Within a slice, the optical field is expanded in the forward and backward propagating eigenmode fields of the corresponding homogeneous waveguide. Evanescent eigenmodes (i.e., high-order modes with an amplitude that decreases exponentially with the distance from the slice interface) are in general needed for field matching at the slice interfaces.

© 1995 Optical Society of America