title: Polarization conversion-based molecular sensing using anisotropic plasmonic metasurfaces.
abstract: Anisotropic media induce changes in the polarization state of transmitted and reflected light. Here we combine this effect with the refractive index sensitivity typical of plasmonic nanoparticles to experimentally demonstrate self-referenced single wavelength refractometric sensing based on polarization conversion. We fabricated anisotropic plasmonic metasurfaces composed of gold dimers and, as a proof of principle, measured the changes in the rotation of light polarization induced by biomolecular adsorption with a surface sensitivity of 0.2 ng cm(-2). We demonstrate the possibility of miniaturized sensing and we show that experimental results can be reproduced by analytical theory. Various ways to increase the sensitivity and applicability of the sensing scheme are discussed.
authors.affiliation: Department of Physics, Chalmers University of Technology, 41296 Göteborg, Sweden. ruggero.verre@chalmers.se mikael.kall@chalmers.se.
authors.forename: R
authors.initials: R
authors.lastname: Verre
authors.affiliation: Department of Physics, Chalmers University of Technology, 41296 Göteborg, Sweden. ruggero.verre@chalmers.se mikael.kall@chalmers.se and CIC nanoGUNE, E-20018 Donostia-San Sebastian, Spain.
authors.forename: N
authors.initials: N
authors.lastname: Maccaferri
authors.affiliation: School of Physics and Center for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College, The University of Dublin, Dublin 2, Ireland.
authors.forename: K
authors.initials: K
authors.lastname: Fleischer
authors.affiliation: Department of Physics, Chalmers University of Technology, 41296 Göteborg, Sweden. ruggero.verre@chalmers.se mikael.kall@chalmers.se.
authors.forename: M
authors.initials: M
authors.lastname: Svedendahl
authors.affiliation: Department of Physics, Chalmers University of Technology, 41296 Göteborg, Sweden. ruggero.verre@chalmers.se mikael.kall@chalmers.se.
authors.forename: N
authors.initials: N
authors.lastname: Odebo Länk
authors.affiliation: Department of Physics, Chalmers University of Technology, 41296 Göteborg, Sweden. ruggero.verre@chalmers.se mikael.kall@chalmers.se.
authors.forename: A
authors.initials: A
authors.lastname: Dmitriev
authors.affiliation: CIC nanoGUNE, E-20018 Donostia-San Sebastian, Spain and IKERBASQUE, Basque Foundation for Science, E-48013 Bilbao, Spain.
authors.forename: P
authors.initials: P
authors.lastname: Vavassori
authors.affiliation: School of Physics and Center for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College, The University of Dublin, Dublin 2, Ireland.
authors.forename: I V
authors.initials: IV
authors.lastname: Shvets
authors.affiliation: Department of Physics, Chalmers University of Technology, 41296 Göteborg, Sweden. ruggero.verre@chalmers.se mikael.kall@chalmers.se.
authors.forename: M
authors.initials: M
authors.lastname: Käll