title: Beaming Visible Light with a Plasmonic Aperture Antenna.
abstract: We investigate experimentally the parameter space defining, in the visible range, the far-field diffraction properties of a single circular subwavelength aperture surrounded by periodic circular grooves milled on a metallic film. Diffraction patterns emerging from such an antenna are recorded under parallel- and perpendicular-polarized illumination at a given illumination wavelength. By monitoring the directivity and the gain of the antenna with respect to a single aperture, we point out the role played by the near-field surface plasmon excitations. The results can be analyzed through a Huygens-Fresnel model, accounting for the coherent interaction between the field radiated by the hole and the plasmonic field, propagating along the antenna surface and diffracted away in free space.
authors.affiliation: ISIS, University of Strasbourg and CNRS (UMR 7006) , 8 Allée Gaspard Monge, 67083 Strasbourg, France.
authors.forename: Jue-Min
authors.initials: JM
authors.lastname: Yi
authors.affiliation: CEMES, University of Toulouse and CNRS (UPR 8011) , 29 Rue Jeanne Marvig, 31055 Toulouse, France.
authors.forename: Aurélien
authors.initials: A
authors.lastname: Cuche
authors.affiliation: ISIS, University of Strasbourg and CNRS (UMR 7006) , 8 Allée Gaspard Monge, 67083 Strasbourg, France.
authors.forename: Eloïse
authors.initials: E
authors.lastname: Devaux
authors.affiliation: ISIS, University of Strasbourg and CNRS (UMR 7006) , 8 Allée Gaspard Monge, 67083 Strasbourg, France.
authors.forename: Cyriaque
authors.initials: C
authors.lastname: Genet
authors.affiliation: ISIS, University of Strasbourg and CNRS (UMR 7006) , 8 Allée Gaspard Monge, 67083 Strasbourg, France.
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Ebbesen
keywords: antenna directivity ; antenna gain; nanoantenna; subwavelength aperture; surface plasmons