title: Directional out-coupling of light from a plasmonic nanowire-nanoparticle junction.
abstract: We experimentally show how a single Ag nanoparticle (NP) coupled to an Ag nanowire (NW) can convert propagating surface plasmon polaritons to directional photons. By employing dual-excitation Fourier microscopy with spatially filtered collection-optics, we show single- and dual-directional out-coupling of light from NW-NP junction for plasmons excited through glass-substrate and air-superstrate. Furthermore, we show NW-NP junction can influence the directionality of molecular-fluorescence emission, thus functioning as an optical antenna. The results discussed herein may have implications in realizing directional single-photon sources and quantum plasmon circuitry.
authors.forename: Danveer
authors.initials: D
authors.lastname: Singh
authors.forename: Arindam
authors.initials: A
authors.lastname: Dasgupta
authors.forename: V G
authors.initials: VG
authors.lastname: Aswathy
authors.forename: Ravi P N
authors.initials: RP
authors.lastname: Tripathi
authors.forename: G V
authors.initials: GV
authors.lastname: Pavan Kumar