title: Tunable directive radiation of surface-plasmon diffraction gratings.
abstract: We experimentally demonstrate tunable radiation from a periodic array of plasmonic nanoscatterers, tailored to convert surface plasmon polaritons into directive leaky modes. Extending our previous studies on efficient directional beaming based on leaky-wave radiation from periodic gratings driven by a subwavelength slit, we experimentally show dynamic beam sweeping by tuning the directional leaky-wave mechanism in real-time. Two alternative tuning mechanisms, wavelength- and index-mediated beam sweeping, are employed to modify the relative phase of scattered light at each grating edge and provide the required modification of the radiation angle.
authors.affiliation: Department of Electrical and Computer Engineering, 1 University Station, Austin, TX 78712, USA.
authors.forename: Youngkyu
authors.initials: Y
authors.lastname: Lee
authors.forename: Kazunori
authors.initials: K
authors.lastname: Hoshino
authors.forename: Andrea
authors.initials: A
authors.lastname: Alù
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Zhang
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D008027:Light; D012031:Refractometry / Q000295:instrumentation*; D012542:Scattering, Radiation; D020349:Surface Plasmon Resonance / Q000295:instrumentation*