Plasmonic response in one- and two-dimensional periodic structures of metallic cylinders

The frequency selective behavior of photonic and plasmonic crystals has attracted considerable attention over the past years. We have investigated two- and three-dimensional structures of metallic rods with a small distance compared to their diameter with a one-and two-dimensional periodicity. Under transverse magnetic (TM) incidence of terahertz (THz) radiation no transmission can be observed, while under transverse electric (TE) incidence the structures presented here show plasmonic behaviour, which leads to an effective plasma frequency. The effective plasma frequency for different rod diameters and geometries is determined with a simple model and compared to numerical simulations and experimental results.