Planar photonic crystal gradient index lens, simulated with a finite difference time domain method

Abstract

We demonstrate the performance of a planar gradient index (GRIN) lens in a two-dimensional photonic crystal. The gradient index is achieved by spatially varying the air-hole radius in the photonic crystal, resulting in a smooth variation of the effective refractive index. We simulate the GRIN lens using a two-dimensional finite difference time domain method to show that it performs as conventional GRIN lenses do. Some of the differences between conventional GRIN lenses and the photonic crystal GRIN lens are discussed.