title: Transition from isolated to collective modes in plasmonic oligomers.
abstract: We demonstrate the transition from isolated to collective optical modes in plasmonic oligomers. Specifically, we investigate the resonant behavior of planar plasmonic hexamers and heptamers with gradually decreasing the interparticle gap separation. A pronounced Fano resonance is observed in the plasmonic heptamer for separations smaller than 60 nm. The spectral characteristics change drastically upon removal of the central nanoparticle. Our work paves the road toward complex hierarchical plasmonic oligomers with tailored optical properties.
authors.affiliation: 4. Physikalisches Institut and Research Center Scope, Universitat Stuttgart, Stuttgart, Germany.
authors.forename: Mario
authors.initials: M
authors.lastname: Hentschel
authors.forename: Michael
authors.initials: M
authors.lastname: Saliba
authors.forename: Ralf
authors.initials: R
authors.lastname: Vogelgesang
authors.forename: Harald
authors.initials: H
authors.lastname: Giessen
authors.forename: A Paul
authors.initials: AP
authors.lastname: Alivisatos
authors.forename: Na
authors.initials: N
authors.lastname: Liu