title: Direct characterization of plasmonic slot waveguides and nanocouplers.
abstract: We demonstrate the use of amplitude- and phase-resolved near-field mapping for direct characterization of plasmonic slot waveguide mode propagation and excitation with nanocouplers in the telecom wavelength range. We measure mode's propagation length, effective index and field distribution and directly evaluate the relative coupling efficiencies for various couplers configurations. We report 26- and 15-fold improvements in the coupling efficiency with two serially connected dipole and modified bow-tie antennas, respectively, as compared to that of the short-circuited waveguide termination.
authors.affiliation: DTU Fotonik, Technical University of Denmark , Oersteds pl. 343, Kongens Lyngby DK-2800, Denmark.
authors.forename: Andrei
authors.initials: A
authors.lastname: Andryieuski
authors.forename: Vladimir A
authors.initials: VA
authors.lastname: Zenin
authors.forename: Radu
authors.initials: R
authors.lastname: Malureanu
authors.forename: Valentyn S
authors.initials: VS
authors.lastname: Volkov
authors.forename: Sergey I
authors.initials: SI
authors.lastname: Bozhevolnyi
authors.forename: Andrei V
authors.initials: AV
authors.lastname: Lavrinenko