Enhanced attenuation due to lattice resonances in a two-dimensional plasma photonic crystal

Abstract

We describe the experimental generation of a deep attenuation band in a finite size (7 × 7) two-dimensional photonic crystal constructed from an array of gaseous plasma columns. The attenuation band, centered at approximately 6 GHz, is due to the lattice resonance between the localized surface plasmon modes at the edge of the plasma columns and the internal Bragg fields of the photonic crystal. The attenuation band has a nearly 40 dB floor with Q ≈ 1. Enhancements are seen in the extinction of normal incidence transverse electric waves when the localized surface plasmon modes of the plasma columns are shifted into the vicinity of the photonic crystal Bragg resonances. Simulations and experiments are in reasonable agreement and confirm the appearance of a Fano-like profile with deep and broad extinction bands. The broadening of the spectra as surface plasmon modes come into coincidence with Bragg gaps suggests that the Bragg fields couple strongly into the radiating dipoles to drive enhanced damping of the photonic crystal resonance.