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Title: Nanoporous gold nanoleaf as tunable metamaterial
Abstract We have studied optical properties of single-layer and multi-fold nanoporous gold leaf (NPGL) metamaterials and observed highly unusual transmission spectra composed of two well-resolved peaks. We explain this phenomenon in terms of a surface plasmon absorption band positioned on the top of a broader transmission band, the latter being characteristic of both homogeneous “solid” and inhomogeneous “diluted” Au films. The transmission spectra of NPGL metamaterials were shown to be controlled by external dielectric environments, e.g. water and applied voltage in an electrochemical cell. This paves the road to numerous functionalities of the studied tunable and active metamaterials, including control of spontaneous emission, energy transfer and many others.
Authors:
; ; ; ; ; ; ; ;
Award ID(s):
1830886 1856515
Publication Date:
NSF-PAR ID:
10273693
Journal Name:
Scientific Reports
Volume:
11
Issue:
1
ISSN:
2045-2322
Sponsoring Org:
National Science Foundation
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