Metallic Spiral Three-Dimensional Photonic Crystal with a Full Band Gap at Optical Communication Wavelengths

The optical properties of a gold spiral photonic crystal (PC) were studied numerically and a full 3-D band gap at near infrared wavelengths was found. This band gap, ranging from 1.2 to 1.8 m in wavelength, covers all the second and third telecom windows used in optical fiber communications. Chiral and other optical properties were also discussed. There is a very high absorption at the band gap edge due to the retarded speed of light and an abnormal high transmission outside the band gap contributed by surface plasmon polaritons. Both right circular polarized (RCP) and left circular polarized (LCP) light are studied and great diversities were found in certain regions of the spectrum. These optical properties maintain within large incident angles.