Transmission through and wave guidance on metal plates perforated by periodic arrays of through-holes of subwavelength coaxial cross-section

Perfect electrically conducting (PEC) plates perforated by doubly periodic arrays of through-holes of subwavelength coaxial cross-section permit enhanced transmission of plane waves and support surface wave guidance. The transmission enhancement is attributed to coupling of free-space fields to TEM and TE11 modal fields in holes and occurs via two distinct mechanisms. The first couples incident fields to local resonances (cavity modes) supported by individual holes. The second couples scattered fields (diffraction modes) to global resonances (surface waves). The surface waves arise due to strong interactions between the holes and can have a large propagation wavenumber. The presented PEC model is adequate in the microwave and terahertz regimes and insights into related wave phenomena at optical frequencies. (C) 2007 Wiley Periodicals, Inc.