Zero Frequency Spectrum of 3-D Metal Photonic Crystals Obtained by the 3-D Kronig–Penney Model

Abstract

We demonstrate in this work the possibility of the existence of ultrashort (dark) pure electrical modes at extremely low frequencies in a system of metallic nanospheres inserted into a dielectric material. These modes resemble usual modes of photonic crystals, but they do not have counterpart for single nanospheres.