Fano interference in supported gold nanosandwiches with weakly coupled nanodisks
Journal article, 2012

We studied the far-field optical response of supported gold-silica-gold nanosandwiches using spectroscopic ellipsometry, reflectance and transmittance measurements. Although transmittance data clearly shows that the gold nanodisks in the sandwich structure interact very weakly, oblique reflectance spectra of s- and p-polarized light show clearly asymmetric line-shapes of the Fano type. However, all experimental results are very well described by modeling the gold nanodisks as oblate spheroids and by employing a 2 x 2 scattering matrix formulation of the Fresnel coefficients provided by an island film theory. In particular, the Fano asymmetry can be explained in terms of interference between the scattered waves from the decoupled nanodisks in the spectral range limited by their respective plasmon resonances. We also show that the reflectance and ellipsometry spectra can be described by a three-layer system with uniaxial effective dielectric functions.

films

plasmons

asymmetry

resonances

nanostructures

optical-properties

shape

metamaterials

Author

A. Mendoza-Galvan

Centro de Investigacion y de Estudios Avanzados Centro de Investigacion y de Estudios Avanzados (CINVESTAV)

K. Järrendahl

Linköping University

Alexander Dmitriev

Chalmers, Applied Physics, Bionanophotonics

Tavakol Pakizeh

K. N. Toosi University of Technology

Mikael Käll

Chalmers, Applied Physics, Bionanophotonics

H Arwin

Linköping University

Optics Express

1094-4087 (ISSN)

Vol. 20 28 29646-29658

Subject Categories

Physical Sciences

DOI

10.1364/OE.20.029646

More information

Latest update

2/28/2018