title: Dual Color Plasmonic Pixels Create a Polarization Controlled Nano Color Palette.
abstract: Color filters based upon nanostructured metals have garnered significant interest in recent years, having been positioned as alternatives to the organic dye-based filters which provide color selectivity in image sensors, as nonfading "printing" technologies for producing images with nanometer pixel resolution, and as ultra-high-resolution, small foot-print optical storage and encoding solutions. Here, we demonstrate a plasmonic filter set with polarization-switchable color properties, based upon arrays of asymmetric cross-shaped nanoapertures in an aluminum thin-film. Acting as individual color-emitting nanopixels, the plasmonic cavity-apertures have dual-color selectivity, transmitting one of two visible colors, controlled by the polarization of the white light incident on the rear of the pixel and tuned by varying the critical dimensions of the geometry and periodicity of the array. This structural approach to switchable optical filtering enables a single nanoaperture to encode two information states within the same physical nanoaperture, an attribute we use here to create micro image displays containing duality in their optical information states.
authors.affiliation: Biomedical Engineering Research Division, School of Engineering, University of Glasgow , Rankine Building, Glasgow G12 8LT, United Kingdom.
authors.forename: Zhibo
authors.initials: Z
authors.lastname: Li
authors.affiliation: Biomedical Engineering Research Division, School of Engineering, University of Glasgow , Rankine Building, Glasgow G12 8LT, United Kingdom.
authors.forename: Alasdair W
authors.initials: AW
authors.lastname: Clark
authors.affiliation: Biomedical Engineering Research Division, School of Engineering, University of Glasgow , Rankine Building, Glasgow G12 8LT, United Kingdom.
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Cooper
keywords: color filter; color printing; metasurfaces; nanocavity apertures; nanoholes; nanoplasmonics; plasmonic pixels