Nanostructures with chiral geometries exhibit strong polarization rotation. However, achieving reversible modulation of chirality and polarization rotation in device-friendly solid-state films is difficult for rigid materials. Here, we describe nanocomposites, made by conformally coating twisted elastic substrates with films assembled layer-by-layer from plasmonic nanocolloids, whose nanoscale geometry and rotatory optical activity can be reversibly reconfigured and cyclically modulated by macroscale stretching, with up to tenfold concomitant increases in ellipticity. We show that the chiroptical activity at 660 nm of gold nanoparticle composites is associated with circular extinction from linear effects. The polarization rotation at 550 nm originates from the chirality of nanoparticle chains with an S-like shape that exhibit a non-planar buckled geometry, with the handedness of the substrate’s macroscale twist determining the handedness of the S-like chains. Chiroptical effects at the nexus of mechanics, excitonics and plasmonics open new operational principles for optical and optoelectronic devices from nanoparticles, carbon nanotubes and other nanoscale components.
Access optionsAccess options
Subscribe to Journal
Get full journal access for 1 year
only $16.58 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Rent or Buy article
Get time limited or full article access on ReadCube.
All prices are NET prices.
Y.K. thanks the Rackham Graduate School for a predoctoral fellowship. O.A. thanks the European Commission for Marie Curie IIF Fellowship PIIF-GA-2012-330513, Nanochirality. This material is based on work partially supported by the Center for Solar and Thermal Energy Conversion, an Energy Frontier Research Center funded by the US Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0000957. We acknowledge support from NSF under grant ECS-0601345; CBET 0933384; CBET 0932823; and CBET 1036672. The work is also partially supported by the US Department of Defense under Grant Award No. MURI W911NF-12-1-0407. This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (Ministry of Education) (No. NRF-2015R1D1A1A01058029). We thank the University of Michigan’s Electron Microscopy and Analysis Laboratory (EMAL) for its assistance with electron microscopy, and for NSF grants (numbers DMR-0320740 and DMR-9871177), for funding the FEI Nova Nanolab Dualbeam Focused Ion Beam Workstation and Scanning Electron Microscope and the JEOL 2010F analytical electron microscope used in this work. We also thank EMAL and the College of Engineering for assistance with the Bruker NanoStar Small-Angle X-ray Scattering System. We wish to acknowledge use of the Microscopy & Image-analysis Laboratory (MIL) at the University of Michigan for preparation of STED samples and obtaining images.
About this article
Nature Communications (2017)