Long-Wavelength Optical Properties of a Plasmonic Crystal

The long-wavelength optical properties of a plasmonic crystal composed of gold nanorod particles have been studied. Because of the strong coupling between the incident light and vibrations of free electrons, bulk polariton excitation can be induced and a polaritonic stop band will be created. An analytical model has been established,which was confirmed by the numerical simulations. The similarity between the plasmonic and ionic crystals, as well as various optical properties, may be of both fundamental and practical interests.