title: All-Dielectric Silicon Nanogap Antennas To Enhance the Fluorescence of Single Molecules.
abstract: Plasmonic antennas have a profound impact on nanophotonics as they provide efficient means to manipulate light and enhance light-matter interactions at the nanoscale. However, the large absorption losses found in metals can severely limit the plasmonic applications in the visible spectral range. Here, we demonstrate the effectiveness of an alternative approach using all-dielectric nanoantennas based on silicon dimers to enhance the fluorescence detection of single molecules. The silicon antenna design is optimized to confine the near-field intensity in the 20 nm nanogap and reach a 270-fold fluorescence enhancement in a nanoscale volume of λ(3)/1800 with dielectric materials only. Our conclusions are assessed by combining polarization resolved optical spectroscopy of individual antennas, scanning electron microscopy, numerical simulations, fluorescence lifetime measurements, fluorescence burst analysis, and fluorescence correlation spectroscopy. This work demonstrates that all-silicon nanoantennas are a valid alternative to plasmonic devices for enhanced single molecule fluorescence sensing, with the additional key advantages of reduced nonradiative quenching, negligible heat generation, cost-efficiency, and complementary metal-oxide-semiconductor (CMOS) compatibility.
authors.affiliation: Aix Marseille Univ, CNRS, Centrale Marseille, Institut Fresnel, Marseille, France.|ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology , 08860 Barcelona, Spain.
authors.forename: Raju
authors.initials: R
authors.lastname: Regmi
authors.affiliation: Aix Marseille Univ, CNRS, Centrale Marseille, Institut Fresnel, Marseille, France.
authors.forename: Johann
authors.initials: J
authors.lastname: Berthelot
authors.affiliation: ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology , 08860 Barcelona, Spain.
authors.forename: Pamina M
authors.initials: PM
authors.lastname: Winkler
authors.affiliation: Université Pierre et Marie Curie, CNRS, Institut des NanoSciences de Paris, UMR 7588, 75005 Paris, France.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Mivelle
authors.affiliation: Aix Marseille Univ, CNRS, Centrale Marseille, Institut Fresnel, Marseille, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Proust
authors.affiliation: Aix Marseille Univ, CNRS, CINAM, Marseille, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Bedu
authors.affiliation: Aix Marseille Univ, CNRS, CINAM, Marseille, France.
authors.forename: Igor
authors.initials: I
authors.lastname: Ozerov
authors.affiliation: Aix Marseille Univ, CNRS, Centrale Marseille, Institut Fresnel, Marseille, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Begou
authors.affiliation: Aix Marseille Univ, CNRS, Centrale Marseille, Institut Fresnel, Marseille, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Lumeau
authors.affiliation: Aix Marseille Univ, CNRS, Centrale Marseille, Institut Fresnel, Marseille, France.
authors.forename: Hervé
authors.initials: H
authors.lastname: Rigneault
authors.affiliation: ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology , 08860 Barcelona, Spain.|ICREA, Pg. Lluís Companys 23, 08010 Barcelona, Spain.
authors.forename: María F
authors.initials: MF
authors.lastname: García-Parajó
authors.affiliation: ESPCI Paris, PSL Research University, CNRS, INSERM, Institut Langevin, 75005 Paris, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Bidault
authors.affiliation: Aix Marseille Univ, CNRS, Centrale Marseille, Institut Fresnel, Marseille, France.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Wenger
authors.affiliation: Aix Marseille Univ, CNRS, Centrale Marseille, Institut Fresnel, Marseille, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Bonod
keywords: All-dielectric nanophotonics; Mie scattering; fluorescence enhancement; optical antenna; silicon resonators