title: Reconfigurable optical assembly of nanostructures.
abstract: Arrangements of nanostructures in well-defined patterns are the basis of photonic crystals, metamaterials and holograms. Furthermore, rewritable optical materials can be achieved by dynamically manipulating nanoassemblies. Here we demonstrate a mechanism to configure plasmonic nanoparticles (NPs) in polymer media using nanosecond laser pulses. The mechanism relies on optical forces produced by the interference of laser beams, which allow NPs to migrate to lower-energy configurations. The resulting NP arrangements are stable without any external energy source, but erasable and rewritable by additional recording pulses. We demonstrate reconfigurable optical elements including multilayer Bragg diffraction gratings, volumetric photonic crystals and lenses, as well as dynamic holograms of three-dimensional virtual objects. We aim to expand the applications of optical forces, which have been mostly restricted to optical tweezers. Holographic assemblies of nanoparticles will allow a new generation of programmable composites for tunable metamaterials, data storage devices, sensors and displays.
authors.affiliation: Department of Chemistry, Imperial College London, Exhibition Road, South Kensington, London SW7 2AZ, UK.
authors.forename: Yunuen
authors.initials: Y
authors.lastname: Montelongo
authors.affiliation: Harvard Medical School and Wellman Center for Photomedicine, Massachusetts General Hospital, 65 Landsdowne Street, Cambridge, Massachusetts 02139, USA.
authors.forename: Ali K
authors.initials: AK
authors.lastname: Yetisen
authors.affiliation: Microengineering and Nanotechnology Laboratory, School of Mechanical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
authors.forename: Haider
authors.initials: H
authors.lastname: Butt
authors.affiliation: Harvard Medical School and Wellman Center for Photomedicine, Massachusetts General Hospital, 65 Landsdowne Street, Cambridge, Massachusetts 02139, USA.|Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Seok-Hyun
authors.initials: SH
authors.lastname: Yun