title: Field enhancement in single subwavelength apertures.
abstract: A peak of the detected fluorescence rate per molecule has recently been observed in experiments of fluorescence correlation spectroscopy carried out on subwavelength apertures in metallic screens, a phenomenon that appears at a diameter-to-wavelength ratio below the fundamental mode cutoff. Although the origin of the resonant transmission through a subwavelength aperture has been well explained in terms of excitation of plasmon surface modes on the aperture ridge, the origin of the maximum that occurs at a radius-to-wavelength ratio smaller than 1/4 was not clear. Using a rigorous electromagnetic theory of light diffraction in cylindrical geometry, we show that it is linked to the appearance of the fundamental mode propagating inside the aperture. We obtain good agreement between the theoretical and the experimental results.
authors.affiliation: Institut Fresnel, Domaine Universitaire de Saint Jérôme, Université d'Aix Marseille III, CNRS UMR 6133, 13397 Marseille Cedex 20, France. e.popov@fresnel.fr
authors.forename: Evgeny
authors.initials: E
authors.lastname: Popov
authors.forename: Michel
authors.initials: M
authors.lastname: Nevière
authors.forename: Jérôme
authors.initials: J
authors.lastname: Wenger
authors.forename: Pierre-François
authors.initials: PF
authors.lastname: Lenne
authors.forename: Hervé
authors.initials: H
authors.lastname: Rigneault
authors.forename: Patric
authors.initials: P
authors.lastname: Chaumet
authors.forename: Nicolas
authors.initials: N
authors.lastname: Bonod
authors.forename: José
authors.initials: J
authors.lastname: Dintinger
authors.forename: Thomas
authors.initials: T
authors.lastname: Ebbesen