title: Metal-Dielectric Waveguides for High Efficiency Coupled Emission.
abstract: We report a metal-dielectric planar structure which provides high efficiency coupling of fluorescence at distances over 100 nm away from the metal surface. This hybrid metal-dielectric waveguide (MDW) consists of a continuous metal film coated with a dielectric layer. We observed efficient long-range coupling of Rhodamine B on top of a 130 nm layer of silica resulting in a narrow angular distribution of the emission. The high efficiency radiation through the Ag film appears to be due to coupling of the fluorophore to an optical waveguide mode with a long propagation length and a narrow resonance. The results were consistent with simulations. These multi-layer structures can be made using vapor deposition and/or spin coating and the silica surface can be used for conjugation to biomolecules and surface-selective detection. This simple hybrid metal-dielectric structures provides new opportunities for fluorescence sensing, genomics, proteomics and diagnostics.
authors.affiliation: Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, 725 W. Lombard Street, Baltimore, MD 21201, USA.
authors.forename: Ramachandram
authors.initials: R
authors.lastname: Badugu
authors.affiliation: Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, 725 W. Lombard Street, Baltimore, MD 21201, USA.
authors.forename: Henryk
authors.initials: H
authors.lastname: Szmacinski
authors.affiliation: Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, 725 W. Lombard Street, Baltimore, MD 21201, USA.
authors.forename: Krishanu
authors.initials: K
authors.lastname: Ray
authors.affiliation: Department of Applied Science and Technology, Polytechnic University of Turin, Corso Duca degli Abruzzi 24, 10129 Turin, Italy.
authors.forename: Emiliano
authors.initials: E
authors.lastname: Descrovi
authors.affiliation: Department of Applied Science and Technology, Polytechnic University of Turin, Corso Duca degli Abruzzi 24, 10129 Turin, Italy.
authors.forename: Serena
authors.initials: S
authors.lastname: Ricciardi
authors.affiliation: Institute of Photonics, Department of Optics and Optical Engineering, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Douguo
authors.initials: D
authors.lastname: Zhang
authors.affiliation: School of Science, Southwest University of Science and Technology, Mianyang, Sichuan 621010, China.
authors.forename: Junxue
authors.initials: J
authors.lastname: Chen
authors.affiliation: School of Physics and Information Technology, Shaanxi Normal University, Xi'an 710062, China.
authors.forename: Yiping
authors.initials: Y
authors.lastname: Huo
authors.affiliation: Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, 725 W. Lombard Street, Baltimore, MD 21201, USA.
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Lakowicz
keywords: Metal-dielectric waveguide; Plasmon-controlled fluorescence; Surface plasmon-coupled emission; Surface plasmon-enhanced fluorescence; Total internal reflection; Waveguide-coupled emission