Localized Plasmonic Properties of Subwavelength Geometries Resonating at Terahertz Frequencies

A review of localized plasmonic properties of 2-D terahertz (THz) metallic geometries is presented. The high electric conductivity of metals in the THz regime enables fascinating plasmonic behaviors observed in metallic structures of subwavelength dimensions. Strong electric field enhancement was demonstrated in arrays of various subwavelength metallic particles including patches, rings, and ring-patch coaxials. We also show that periodic arrays of integrated coaxials comprised of patches and subwavelength holes not only resulted in a factor-of-eight increase in normalized transmittance compared to that of the hole-only counterpart, but also tailored polarization dependent transmission discrepancy encountered in arrays of rectangular holes. The localized plasmonic properties and the resulted electric field enhancement will find fascinating applications in THz sensing, spectroscopy, and integrated components.