title: Visible-frequency hyperbolic metasurface.
abstract: Metamaterials are artificial optical media composed of sub-wavelength metallic and dielectric building blocks that feature optical phenomena not present in naturally occurring materials. Although they can serve as the basis for unique optical devices that mould the flow of light in unconventional ways, three-dimensional metamaterials suffer from extreme propagation losses. Two-dimensional metamaterials (metasurfaces) such as hyperbolic metasurfaces for propagating surface plasmon polaritons have the potential to alleviate this problem. Because the surface plasmon polaritons are guided at a metal-dielectric interface (rather than passing through metallic components), these hyperbolic metasurfaces have been predicted to suffer much lower propagation loss while still exhibiting optical phenomena akin to those in three-dimensional metamaterials. Moreover, because of their planar nature, these devices enable the construction of integrated metamaterial circuits as well as easy coupling with other optoelectronic elements. Here we report the experimental realization of a visible-frequency hyperbolic metasurface using single-crystal silver nanostructures defined by lithographic and etching techniques. The resulting devices display the characteristic properties of metamaterials, such as negative refraction and diffraction-free propagation, with device performance greatly exceeding those of previous demonstrations. Moreover, hyperbolic metasurfaces exhibit strong, dispersion-dependent spin-orbit coupling, enabling polarization- and wavelength-dependent routeing of surface plasmon polaritons and two-dimensional chiral optical components. These results open the door to realizing integrated optical meta-circuits, with wide-ranging applications in areas from imaging and sensing to quantum optics and quantum information science.
authors.affiliation: 1] Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA [2] Department of Physics, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA.
authors.forename: Alexander A
authors.initials: AA
authors.lastname: High
authors.affiliation: School of Engineering and Applied Sciences, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Devlin
authors.affiliation: School of Engineering and Applied Sciences, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA.
authors.forename: Alan
authors.initials: A
authors.lastname: Dibos
authors.affiliation: Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Polking
authors.affiliation: Department of Physics, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA.
authors.forename: Dominik S
authors.initials: DS
authors.lastname: Wild
authors.affiliation: 1] Department of Physics, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA [2] Department of Physics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
authors.forename: Janos
authors.initials: J
authors.lastname: Perczel
authors.affiliation: 1] Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA [2] Department of Physics, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA.
authors.forename: Nathalie P
authors.initials: NP
authors.lastname: de Leon
authors.affiliation: Department of Physics, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA.
authors.forename: Mikhail D
authors.initials: MD
authors.lastname: Lukin
authors.affiliation: 1] Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA [2] Department of Physics, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA.
authors.forename: Hongkun
authors.initials: H
authors.lastname: Park