Optical response of electro-tuneable 3D superstructures of plasmonic nanoparticles self-assembling on transparent columnar electrodes
File(s)
Published version
Author(s)
Kornyshev, Alexei
Sikdar, Debabrata
Weir, Hayley
Type
Journal Article
Abstract
Electrically tuneable, guided self-assembly of plasmonic nanoparticles (NPs) at polarized, patterned solid–liquid interfaces could enable numerous platforms for designing nanoplasmonic optical devices with new tuneable functionalities. Here, we propose a unique design of voltage-controlled guided 3D self-assembly of plasmonic NPs on transparent electrodes, patterned as columnar structures — arrays of vertical nanorods. NP assembly on the electrified surfaces of those columnar structures allows formation of a 3D superstructure of NPs, comprising stacking up of NPs in the voids between the columns, forming multiple NP-layers. A comprehensive theoretical model, based on quasi-static effective medium theory and multilayer Fresnel reflection scheme, is developed and verified against full-wave simulations for obtaining optical responses — reflectance, transmittance, and absorbance — from such systems of 3D self-assembled NPs. With a specific example of small gold nanospheres, self-assembling on polarized zinc oxide columns, we show that the reflectance spectrum can be controlled by the number of stacked NP-layers. Numerical simulations show that peak reflectance can be enhanced up to ~1.7 times, along with spectral broadening by a factor of ~2 — allowing wide range tuning of optical reflectivity. Smaller NPs with superior mobility would be preferable over large NPs for realizing such devices for novel photonic and sensing applications.
Date Issued
2019-09-04
Date Acceptance
2019-08-14
Citation
Optics Express, 2019, 19 (19), pp.26483-26498
ISSN
1094-4087
Publisher
Optical Society of America (OSA)
Start Page
26483
End Page
26498
Journal / Book Title
Optics Express
Volume
19
Issue
19
Copyright Statement
© 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement (https://doi.org/10.1364/OA_License_v1).
Identifier
https://www.imperial.ac.uk/people/a.kornyshev
Subjects
Science & Technology
Physical Sciences
Optics
NANOPLASMONIC MIRROR
GOLD NANORODS
ZNO NANORODS
BROAD-BAND
SOLAR
ENHANCEMENT
COMPOSITE
SURFACES
DESIGN
LIGHT
Optics
0205 Optical Physics
1005 Communications Technologies
0906 Electrical and Electronic Engineering
Publication Status
Published
Article Number
OpEx 371551
Date Publish Online
2019-09-04