title: Multipolar interference for directed light emission.
abstract: By directing light, optical antennas can enhance light-matter interaction and improve the efficiency of nanophotonic devices. Here we exploit the interference among the electric dipole, quadrupole, and magnetic dipole moments of a split-ring resonator to experimentally realize a compact directional optical antenna. This single-element antenna design robustly directs emission even when covered with nanometric emitters at random positions, outperforming previously demonstrated nanoantennas with a bandwidth of 200 nm and a directivity of 10.1 dB from a subwavelength structure. The advantages of this approach bring directional optical antennas closer to practical applications.
authors.affiliation: ICFO-Institut de Ciencies Fotoniques , Mediterranean Technology Park, 08860 Castelldefels (Barcelona), Spain.
authors.forename: Ion M
authors.initials: IM
authors.lastname: Hancu
authors.forename: Alberto G
authors.initials: AG
authors.lastname: Curto
authors.forename: Marta
authors.initials: M
authors.lastname: Castro-López
authors.forename: Martin
authors.initials: M
authors.lastname: Kuttge
authors.forename: Niek F
authors.initials: NF
authors.lastname: van Hulst