title: SERS Amplification from Self-Organized Arrays of Plasmonic Nanocrescents.
abstract: We report on the surface-enhanced Raman scattering (SERS) efficiency of self-organized arrays of Au nanocrescents confined on monolayers of polystyrene nanospheres. A dichroic SERS emission in the visible spectrum is observed due to the selective excitation of a localized surface plasmon (LSP) resonance along the "short axis" of the Au nanocrescents. Under these conditions SERS signal amplifications in the range of 10(3) have been observed with respect to a flat reference Au film. The far field and near field plasmonic response of Au nanocrescent arrays have been investigated as a function of the metal dose deposited onto the polymeric spheres. In this way, we show the possibility of simply tailoring the SERS emission by engineering the morphology of the plasmonic nanocrescents. We highlight the SERS activity of chains of satellite nanoclusters that decorate the border of each connected crescent and sustain isotropic high energy LSP resonances in the visible spectrum.
authors.affiliation: Department of Physics, University of Genova , Via Dodecaneso 33, I-16146 Genova, Italy.
authors.forename: Maria Caterina
authors.initials: MC
authors.lastname: Giordano
authors.affiliation: CNR IPCF Institute for Chemical and Physical processes , Viale F. Stagno D'Alcontres 37, I-98156 Messina, Italy.|School of Doctorate in Physics, University of Messina , Viale F. Stagno D'Alcontres 31, I-98156 Messina, Italy.
authors.forename: Antonino
authors.initials: A
authors.lastname: Foti
authors.affiliation: CNR IPCF Institute for Chemical and Physical processes , Viale F. Stagno D'Alcontres 37, I-98156 Messina, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Messina
authors.affiliation: CNR IPCF Institute for Chemical and Physical processes , Viale F. Stagno D'Alcontres 37, I-98156 Messina, Italy.
authors.forename: Pietro Giuseppe
authors.initials: PG
authors.lastname: Gucciardi
authors.affiliation: Department of Chemistry and Industrial Chemistry, University of Genova Via Dodecaneso 31, 16146, Genova, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Comoretto
authors.affiliation: Department of Physics, University of Genova , Via Dodecaneso 33, I-16146 Genova, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Buatier de Mongeot
keywords: biosensing; nanophotonics; nanostructures; plasmonic nanoantennas; polymer nanosphere arrays; surface-enhanced Raman scattering