title: Giant Nonlinear Optical Activity of Achiral Origin in Planar Metasurfaces with Quadratic and Cubic Nonlinearities.
abstract: 3D chirality is shown to be unnecessary for introducing strong circular dichroism for harmonic generations. Specifically, near-unity circular dichroism for both second-harmonic generation and third-harmonic generations is demonstrated on suitably designed ultrathin plasmonic metasurfaces with only 2D planar chirality. The study opens up new routes for designing chip-type biosensing platform, which may allow for highly sensitive detection of bio- and chemical molecules with weak chirality.
authors.affiliation: School of Physics and Astronomy, University of Birmingham, Birmingham, B15 2TT, UK.|Department of Physics, Hong Kong Baptist University, Kowloon Tong, Hong Kong.
authors.forename: Shumei
authors.initials: S
authors.lastname: Chen
authors.affiliation: Department of Physics, University of Paderborn, Warburger Straße 100, Paderborn, D-33098, Germany.
authors.forename: Franziska
authors.initials: F
authors.lastname: Zeuner
authors.affiliation: Department of Electronic and Electrical Engineering, University College London, Torrington Place, London, WC1 E7JE, UK.
authors.forename: Martin
authors.initials: M
authors.lastname: Weismann
authors.affiliation: Department of Physics, University of Paderborn, Warburger Straße 100, Paderborn, D-33098, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Reineke
authors.affiliation: School of Physics and Astronomy, University of Birmingham, Birmingham, B15 2TT, UK.
authors.forename: Guixin
authors.initials: G
authors.lastname: Li
authors.affiliation: Department of Physics, University of Bath, Claverton Down, Bath, BA2 7AY, UK.
authors.forename: Ventsislav Kolev
authors.initials: VK
authors.lastname: Valev
authors.affiliation: Department of Physics, Hong Kong Baptist University, Kowloon Tong, Hong Kong.
authors.forename: Kok Wai
authors.initials: KW
authors.lastname: Cheah
authors.affiliation: Department of Electronic and Electrical Engineering, University College London, Torrington Place, London, WC1 E7JE, UK.
authors.forename: Nicolae Coriolan
authors.initials: NC
authors.lastname: Panoiu
authors.affiliation: Department of Physics, University of Paderborn, Warburger Straße 100, Paderborn, D-33098, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Zentgraf
authors.affiliation: School of Physics and Astronomy, University of Birmingham, Birmingham, B15 2TT, UK.
authors.forename: Shuang
authors.initials: S
authors.lastname: Zhang
mesh_terms: D002942:Circular Dichroism; D008027:Light; D008958:Models, Molecular; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry*; D017711:Nonlinear Dynamics; D055620:Optical Phenomena; D012399:Rotation; D013499:Surface Properties
keywords: circular dichroism; metasurfaces; nonlinear optics; plasmonic