Abstract

We show that an omnidirectional point source embedded in a photonic crystal designed to possess a small and negative index of refraction [1] becomes in a highly-directional beam because of the photonic crystal (see Fig. 1). The slab makes a filtering of high transverse wavevectors of the diverging beam. The predicted phenomenon is demonstrated at microwave frequencies (~13 GHz) using a two-dimensional photonic crystal made of alumina rods.

© 2007 IEEE