title: Chiral plasmonic DNA nanostructures with switchable circular dichroism.
abstract: Circular dichroism spectra of naturally occurring molecules and also of synthetic chiral arrangements of plasmonic particles often exhibit characteristic bisignate shapes. Such spectra consist of peaks next to dips (or vice versa) and result from the superposition of signals originating from many individual chiral objects oriented randomly in solution. Here we show that by first aligning and then toggling the orientation of DNA-origami-scaffolded nanoparticle helices attached to a substrate, we are able to reversibly switch the optical response between two distinct circular dichroism spectra corresponding to either perpendicular or parallel helix orientation with respect to the light beam. The observed directional circular dichroism of our switchable plasmonic material is in good agreement with predictions based on dipole approximation theory. Such dynamic metamaterials introduce functionality into soft matter-based optical devices and may enable novel data storage schemes or signal modulators.
authors: Fakultät für Physik and Center for Nanoscience, Ludwig-Maximilians-Universität, 80539 München, Germany.
authors: Robert
authors: R
authors: Schreiber
authors: Department of Electrical and Computer Engineering, Boise State University, Boise, Idaho 83725, USA.
authors: Ngoc
authors: N
authors: Luong
authors: Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701, USA.
authors: Zhiyuan
authors: Z
authors: Fan
authors: Max-Planck-Institute for Intelligent Systems, 70569 Stuttgart, Germany.
authors: Anton
authors: A
authors: Kuzyk
authors: Fakultät für Physik and Center for Nanoscience, Ludwig-Maximilians-Universität, 80539 München, Germany.
authors: Philipp C
authors: PC
authors: Nickels
authors: Fakultät für Physik and Center for Nanoscience, Ludwig-Maximilians-Universität, 80539 München, Germany.
authors: Tao
authors: T
authors: Zhang
authors: Fakultät für Physik and Center for Nanoscience, Ludwig-Maximilians-Universität, 80539 München, Germany.
authors: David M
authors: DM
authors: Smith
authors: Department of Electrical and Computer Engineering, Boise State University, Boise, Idaho 83725, USA.
authors: Bernard
authors: B
authors: Yurke
authors: Department of Electrical and Computer Engineering, Boise State University, Boise, Idaho 83725, USA.
authors: Wan
authors: W
authors: Kuang
authors: Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701, USA.
authors: Alexander O
authors: AO
authors: Govorov
authors: Fakultät für Physik and Center for Nanoscience, Ludwig-Maximilians-Universität, 80539 München, Germany.
authors: Tim
authors: T
authors: Liedl
mesh_terms: D002942:Circular Dichroism; D004247:DNA / Q000737:chemistry*; D004277:DNA, Single-Stranded / Q000737:chemistry; D005898:Glass; D006046:Gold / Q000737:chemistry; D008422:Materials Testing; D053768:Metal Nanoparticles / Q000737:chemistry; D053761:Nanocomposites / Q000737:chemistry*; D036103:Nanotechnology; D055095:Optics and Photonics; D010316:Particle Size; D012815:Signal Processing, Computer-Assisted; D012996:Solutions; D013237:Stereoisomerism; D013499:Surface Properties
chemical_list: D004277:DNA, Single-Stranded; D012996:Solutions; D006046:Gold; D004247:DNA