title: Plasmon coupling in silver nanocube dimers: resonance splitting induced by edge rounding.
abstract: Absolute extinction cross sections of individual silver nanocube dimers are measured using spatial modulation spectroscopy in correlation with their transmission electron microscopy images. For very small interparticle distances and an incident light polarized along the dimer axis, we give evidence for a clear splitting of the main dipolar surface plasmon resonance which is found to be essentially induced by cube edge rounding effects. Supported by discrete dipole approximation and finite element method calculations, this phenomenon highlights the high sensitivity of the plasmonic coupling to the exact shape of the effective capacitor formed by the facing surfaces of both particles, especially in the regime of very close proximity.
authors.affiliation: Laboratoire de Spectrométrie Ionique et Moléculaire (UMR 5579) 43, CNRS, Université Lyon 1, Bld du 11 Novembre 1918, 69622 Villeurbanne Cedex, France.
authors.forename: Nadia
authors.initials: N
authors.lastname: Grillet
authors.forename: Delphine
authors.initials: D
authors.lastname: Manchon
authors.forename: Franck
authors.initials: F
authors.lastname: Bertorelle
authors.forename: Christophe
authors.initials: C
authors.lastname: Bonnet
authors.forename: Michel
authors.initials: M
authors.lastname: Broyer
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Cottancin
authors.forename: Jean
authors.initials: J
authors.lastname: Lermé
authors.forename: Matthias
authors.initials: M
authors.lastname: Hillenkamp
authors.forename: Michel
authors.initials: M
authors.lastname: Pellarin
mesh_terms: D003198:Computer Simulation; D019281:Dimerization; D008027:Light; D008422:Materials Testing; D008956:Models, Chemical; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D012542:Scattering, Radiation; D012834:Silver / Q000737:chemistry*; D020349:Surface Plasmon Resonance / Q000379:methods*; D013499:Surface Properties
chemical_list: D012834:Silver