title: "Digitally" addressable focusing of light into a subwavelength hot spot.
abstract: We show that a plasmonic metamaterial can act as a far-field to near-field transformer that focuses a free-space beam of light into a subwavelength energy hot spot at a prescribed location with a spot size only a small fraction of the wavelength. The hot spot position on the metamaterial can be prescribed and moved at will from one metamolecule of the array to another in a "digital" fashion simply by modulating the input phase profile, thus providing new opportunities for imaging and optical data processing.
authors.affiliation: Optoelectronics Research Centre and Centre for Photonic Metamaterials, University of Southampton, Southampton SO17 1BJ, United Kingdom.
authors.forename: T S
authors.initials: TS
authors.lastname: Kao
authors.forename: E T F
authors.initials: ET
authors.lastname: Rogers
authors.forename: J Y
authors.initials: JY
authors.lastname: Ou
authors.forename: N I
authors.initials: NI
authors.lastname: Zheludev
mesh_terms: D003198:Computer Simulation; D008027:Light; D008956:Models, Chemical; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D012542:Scattering, Radiation; D012815:Signal Processing, Computer-Assisted; D020349:Surface Plasmon Resonance / Q000379:methods*