3D photonic crystals : Design and simulation

We designed and simulated a photonic crystal realized on silicon on insulator(SOI) layers. The obtained bandgap is centered on the wavelength of 1.55 mum, the spectral region for todaypsilas optical communications. We designed two types of waveguides (tapered and straight) that contain the photonic crystal, and these are to be implemented on SOI wafers. The photonic crystals consists in a square or hexagonal lattice of holes configured in a high refractive index layer deposited on silicon oxide. By using a combination of plane wave expansion (PWE) and finite difference time domain (FDTD) methods we have determined the bandgap of the structure and we have computed the transmission and reflection properties of the system. Using FDTD simulations, we have put in evidence the subwavelength confinement in a waveguide consisting in a line defects realized in the photonic crystal.