Fano interference in supported gold nanosandwiches with weakly coupled nanodisks
2012 (English)In: Optics Express, ISSN 1094-4087, Vol. 20, no 28, 29646-29658 p.Article in journal (Refereed) Published
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 × 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.
Place, publisher, year, edition, pages
2012. Vol. 20, no 28, 29646-29658 p.
Surface plasmons; Anisotropic optical materials; Artificially engineered materials; Ellipsometry and polarimetry; Optical properties.
IdentifiersURN: urn:nbn:se:liu:diva-86702DOI: 10.1364/OE.20.029646ISI: 000314914500055OAI: oai:DiVA.org:liu-86702DiVA: diva2:580445
FunderKnut and Alice Wallenberg Foundation
Funding Agencies|Conacyt-Mexico||Fondo Sectorial de Investigacion para la Educacion|103385|Swedish Foundation for Strategic Research|RMA08|2012-12-212012-12-212013-10-14