title: Quantitative spectroscopy on individual wire, slot, bow-tie, rectangular, and square-shaped optical antennas.
abstract: By using a recently introduced approach combining a focus-modulation technique with a common-path interferometer, we measure quantitatively the extinction, scattering, and absorption cross-section spectra of individual optical antennas. The experimental results on thin-wire antennas, slot antennas, bow-tie antennas, rectangular antennas, and square-shaped antennas resonating at around 1.4 μm wavelength are discussed. We find increased resonant scattering cross sections for the latter four antennas compared to the thin-wire antenna, both in absolute terms and relative to the absorption cross section. The square-shaped antenna's resonant extinction cross section approaches the limit of a coherent point dipole. However, the ratio of the resonant extinction cross section to the geometrical cross section of 38 is largest for the simple thin-wire antenna.
authors: Martin
authors: M
authors: Husnik
authors: Jens
authors: J
authors: Niegemann
authors: Kurt
authors: K
authors: Busch
authors: Martin
authors: M
authors: Wegener
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D008027:Light; D053770:Nanowires; D012542:Scattering, Radiation; D013057:Spectrum Analysis / Q000295:instrumentation*; D020349:Surface Plasmon Resonance / Q000295:instrumentation*