Plasmonic Complex Fluids of Nematiclike and Helicoidal Self-Assemblies of Gold Nanorods with a Negative Order Parameter
2012 (English)In: Physical Review Letters, ISSN 0031-9007, Vol. 109, no 8, 088301- p.Article in journal (Refereed) Published
We describe a soft matter system of self-organized oblate micelles and plasmonic gold nanorods that exhibit a negative orientational order parameter. Because of anisotropic surface anchoring interactions, colloidal gold nanorods tend to align perpendicular to the director describing the average orientation of normals to the discoidal micelles. Helicoidal structures of highly concentrated nanorods with a negative order parameter are realized by adding a chiral additive and are further controlled by means of confinement and mechanical stress. Polarization-sensitive absorption, scattering, and two-photon luminescence are used to characterize orientations and spatial distributions of nanorods. Self-alignment and effective-medium optical properties of these hybrid inorganic-organic complex fluids match predictions of a simple model based on anisotropic surface anchoring interactions of nanorods with the structured host medium.
Place, publisher, year, edition, pages
2012. Vol. 109, no 8, 088301- p.
Liquid-Crystals, Topological Defects, Anisotropic Fluids, Columnar Phase, Alignment, Microscopy
IdentifiersURN: urn:nbn:se:kth:diva-102623DOI: 10.1103/PhysRevLett.109.088301ISI: 000307711300016ScopusID: 2-s2.0-84865261813OAI: oai:DiVA.org:kth-102623DiVA: diva2:555814
QC 201209212012-09-212012-09-212013-11-19Bibliographically approved