Abstract

We show that the propagation of optical beams inside three-dimensional (3D) photonic crystals (PCs) can be efficiently described by an approximate scalar diffraction model. We show that for each polarization, two principal diffractive indices are found describing the beam diffraction along two axes perpendicular to the propagation direction. The main advantage of this model is that it reduces the memory and processing requirements for direct simulations of 3D PCs by converting the problem into an equivalent problem for which simple geometrical optics can be applied. Using this model, we also discuss some unique diffractive phenomena that can be observed by properly engineering the PC structure and its excitation.

© 2007 Optical Society of America