Ideal Dimers of Gold Nanospheres for Precision Plasmonics: Synthesis and Characterization at the Single-Particle Level for Identification of Higher Order Modes

Jun Hee Yoon; Florian Selbach; Ludmilla Langolf; Sebastian Schlücker

doi:10.1002/smll.201702754

Ideal Dimers of Gold Nanospheres for Precision Plasmonics: Synthesis and Characterization at the Single-Particle Level for Identification of Higher Order Modes

Small. 2018 Jan;14(4). doi: 10.1002/smll.201702754. Epub 2017 Nov 27.

Authors

Jun Hee Yoon¹, Florian Selbach¹, Ludmilla Langolf¹, Sebastian Schlücker¹

Affiliation

¹ Physical Chemistry I, Department of Chemistry and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Universitätsstraße 5, 45141, Essen, Germany.

PMID: 29178555
DOI: 10.1002/smll.201702754

Abstract

Ideal dimers comprising gold nanoparticles with a smooth surface and high sphericity are synthesized by a substrate-based assembly strategy with efficient cetyltrimethylammonium bromide removal. An unprecedented structural and plasmonic uniformity at the single-particle level is observed since inhomogeneities resulting from variations in gap morphology are eliminated. Single ideal dimers are analyzed by polarization-resolved dark-field scattering spectroscopy. Contributions from transverse as well as quadrupolar and octupolar longitudinal plasmon coupling modes can be discriminated because of their orthogonal polarization behavior. The assignment of these higher order coupling modes is supported by computer simulations.

Keywords: CTAB; SERS; assembly; elastic scattering; noble metal nanoparticles.

Publication types

Research Support, Non-U.S. Gov't