title: Symmetry breaking in a plasmonic metamaterial at optical wavelength.
abstract: We numerically study the effect of structural asymmetry in a plasmonic metamaterial made from gold nanowires. It is reported that optically inactive (i.e., optically dark) particle plasmon modes of the symmetric wire lattice are immediately coupled to the radiation field, when a broken structural symmetry is introduced. Such higher order plasmon resonances are characterized by their subradiant nature. They generally reveal long lifetimes and distinct absorption losses. It is shown that the near-field interaction strongly determines these modes.
authors.affiliation: Nanophotonics and Metrology Laboratory, Ecole Polytechnique Fédéral de Lausanne, Lausanne, Switzerland. andre.christ@epfl
authors.forename: André
authors.initials: A
authors.lastname: Christ
authors.forename: Olivier J F
authors.initials: OJ
authors.lastname: Martin
authors.forename: Yasin
authors.initials: Y
authors.lastname: Ekinci
authors.forename: Nikolai A
authors.initials: NA
authors.lastname: Gippius
authors.forename: Sergei G
authors.initials: SG
authors.lastname: Tikhodeev
mesh_terms: D004583:Electrons; D006046:Gold / Q000737:chemistry*; D008280:Magnetics; D053770:Nanowires / Q000737:chemistry; D055095:Optics and Photonics; D013053:Spectrophotometry
chemical_list: D006046:Gold