Macroscopic Layers of Chiral Plasmonic Nanoparticle Oligomers from Colloidal Lithography
Journal article, 2014

Optical near-field coupling between closely spaced plasmonic metal nanoparticles is important to a range of nanophotonic applications of high contemporary interest, including surface-enhanced molecular spectroscopy, nanooptical sensing, and various novel light-harvesting concepts. Here we report on monolayers of chiral heterotrimers and heterotetramers composed of closely spaced silver and/or gold nanodisks of different heights fabricated through facile hole-mask colloidal lithography. These quasi-three-dimensional oligomers are interesting for applications because they exhibit "hot" gaps and crevices of nanometric dimensions, a pronounced circular dichroism, and optical chirality in the visible to near-infrared wavelength range, and they can be produced in large ensembles (>109) of identical orientation. We analyze the optical properties of the samples based on simulation results and find that the circular dichroism is due to strong near-field coupling and intricate phase retardation effects originating in the three-dimensional character of the individual oligomers.



circular dichroism

numerical simulation

optical chirality

hole-mask colloidal lithography


Robin Ogier

Chalmers, Applied Physics, Bionanophotonics

Yurui Fang

Chalmers, Applied Physics, Bionanophotonics

Mikael Svedendahl

Chalmers, Applied Physics, Bionanophotonics

Peter Johansson

Chalmers, Applied Physics, Bionanophotonics

Mikael Käll

Chalmers, Applied Physics, Bionanophotonics

ACS Photonics

2330-4022 (eISSN)

Vol. 1 10 1074-1081

Subject Categories

Nano Technology



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