title: Enhancing second harmonic generation in gold nanoring resonators filled with lithium niobate.
abstract: Plasmonic nanorings provide the unique advantage of a pronounced plasmonic field enhancement inside their core. If filled with a polarizable medium, it may significantly enhance its optical effects. Here, we demonstrate this proposition by filling gold nanorings with lithium niobate. The generated second harmonic signal is compared to the signal originating from an unpatterned lithium niobate surface. Measurements and simulation confirm an enhancement of about 20. Applications requiring nanoscopic localized light sources like fluorescence spectroscopy or quantum communication will benefit from our findings.
authors.affiliation: Institute of Applied Physics, Abbe Center of Photonics, Friedrich-Schiller-University Jena , Max-Wien-Platz 1, 07743 Jena, Germany.
authors.forename: Dennis
authors.initials: D
authors.lastname: Lehr
authors.forename: Jörg
authors.initials: J
authors.lastname: Reinhold
authors.forename: Illia
authors.initials: I
authors.lastname: Thiele
authors.forename: Holger
authors.initials: H
authors.lastname: Hartung
authors.forename: Kay
authors.initials: K
authors.lastname: Dietrich
authors.forename: Christoph
authors.initials: C
authors.lastname: Menzel
authors.forename: Thomas
authors.initials: T
authors.lastname: Pertsch
authors.forename: Ernst-B
authors.initials: EB
authors.lastname: Kley
authors.forename: Andreas
authors.initials: A
authors.lastname: Tünnermann
keywords: Lithium niobate; ion beam enhanced etching; nanorings; plasmonics; second harmonic generation