title: Rainbow radiating single-crystal Ag nanowire nanoantenna.
abstract: Optical antennas interface an object with optical radiation and boost the absorption and emission of light by the objects through the antenna modes. It has been much desired to enhance both excitation and emission processes of the quantum emitters as well as to interface multiwavelength channels for many nano-optical applications. Here we report the experimental implementation of an optical antenna operating in the full visible range via surface plasmon currents induced in a defect-free single-crystalline Ag nanowire (NW). With its atomically flat surface, the long Ag NW reliably establishes multiple plasmonic resonances and produces a unique rainbow antenna radiation in the Fresnel region. Detailed antenna radiation properties, such as radiating near-field patterns and polarization states, were experimentally examined and precisely analyzed by numerical simulations and antenna theory. The multiresonant Ag NW nanoantenna will find superb applications in nano-optical spectroscopy, high-resolution nanoimaging, photovoltaics, and nonlinear signal conversion.
authors.affiliation: Department of Chemistry, KAIST, Daejeon 305-701, Korea.
authors.forename: Taejoon
authors.initials: T
authors.lastname: Kang
authors.forename: Wonjun
authors.initials: W
authors.lastname: Choi
authors.forename: Ilsun
authors.initials: I
authors.lastname: Yoon
authors.forename: Hyoban
authors.initials: H
authors.lastname: Lee
authors.forename: Min-Kyo
authors.initials: MK
authors.lastname: Seo
authors.forename: Q-Han
authors.initials: QH
authors.lastname: Park
authors.forename: Bongsoo
authors.initials: B
authors.lastname: Kim