title: Surface plasmon resonance spectroscopy of single bowtie nano-antennas using a differential reflectivity method.
abstract: We report on the structural and optical properties of individual bowtie nanoantennas both on glass and semiconducting GaAs substrates. The antennas on glass (GaAs) are shown to be of excellent quality and high uniformity reflected by narrow size distributions with standard deviations for the triangle and gap size of = 4.5 nm = 2.6 nm and = 5.4 nm = 3.8 nm, respectively. The corresponding optical properties of individual nanoantennas studied by differential reflection spectroscopy show a strong reduction of the localised surface plasmon polariton resonance linewidth from 0.21 eV to 0.07 eV upon reducing the antenna size from 150 nm to 100 nm. This is attributed to the absence of inhomogeneous broadening as compared to optical measurements on nanoantenna ensembles. The inter-particle coupling of an individual bowtie nanoantenna, which gives rise to strongly localised and enhanced electromagnetic hotspots, is demonstrated using polarization-resolved spectroscopy, yielding a large degree of linear polarization of ρmax ~ 80%. The combination of highly reproducible nanofabrication and fast, non-destructive and non-contaminating optical spectroscopy paves the route towards future semiconductor-based nano-plasmonic circuits, consisting of multiple photonic and plasmonic entities.
authors.affiliation: Walter Schottky Institut and Physik Department, Technische Universität München, Am Coulombwall 4, 85748 Garching b. München, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Kaniber
authors.affiliation: Walter Schottky Institut and Physik Department, Technische Universität München, Am Coulombwall 4, 85748 Garching b. München, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Schraml
authors.affiliation: Walter Schottky Institut and Physik Department, Technische Universität München, Am Coulombwall 4, 85748 Garching b. München, Germany.|Institute for Advanced Study, Technische Universität München, Lichtenbergstrasse 2a, Garching, Germany, 85748.
authors.forename: A
authors.initials: A
authors.lastname: Regler
authors.affiliation: Walter Schottky Institut and Physik Department, Technische Universität München, Am Coulombwall 4, 85748 Garching b. München, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Bartl
authors.affiliation: Walter Schottky Institut and Physik Department, Technische Universität München, Am Coulombwall 4, 85748 Garching b. München, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Glashagen
authors.affiliation: Walter Schottky Institut and Physik Department, Technische Universität München, Am Coulombwall 4, 85748 Garching b. München, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Flassig
authors.affiliation: Walter Schottky Institut and Physik Department, Technische Universität München, Am Coulombwall 4, 85748 Garching b. München, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Wierzbowski
authors.affiliation: Walter Schottky Institut and Physik Department, Technische Universität München, Am Coulombwall 4, 85748 Garching b. München, Germany.|Nanosystems Initiative Munich (NIM), Schellingstraße 4, 80799 München, Germany.
authors.forename: J J
authors.initials: JJ
authors.lastname: Finley