title: Hot Electron Generation and Cathodoluminescence Nanoscopy of Chiral Split Ring Resonators.
abstract: Three-dimensional chiral plasmonic nanostructures have been shown to be able to dramatically boost photon-spin selective light-matter interactions, potentially leading to novel photonics, molecular spectroscopy, and light-harvesting applications based on circularly polarized light. Here, we show that chiral split-ring gold nanoresonators interfaced to a wide band gap semiconductor exhibit a contrast in hot-electron transfer rate between left-handed and right-handed visible light that essentially mimics the far-field circular dichroism of the structures. We trace down the origin of this effect to the differential excitation of the thinnest part of the split-ring structures using dichroic-sensitive cathodoluminescence imaging with nanometer spatial resolution. The results highlight the intricate interplay between the near-field and far-field chiral response of a nanostructure and establishes a clear link to the emerging field of hot carrier plasmonics with numerous potential applications in photocatalysis and solar light harvesting.
authors.affiliation: Department of Physics, Chalmers University of Technology , 412 96 Göteborg, Sweden.
authors.forename: Yurui
authors.initials: Y
authors.lastname: Fang
authors.affiliation: Department of Physics, Chalmers University of Technology , 412 96 Göteborg, Sweden.
authors.forename: Ruggero
authors.initials: R
authors.lastname: Verre
authors.affiliation: Department of Physics, Chalmers University of Technology , 412 96 Göteborg, Sweden.
authors.forename: Lei
authors.initials: L
authors.lastname: Shao
authors.affiliation: Department of Physics and Astronomy, Rice University , 77005 Houston, United States.
authors.forename: Peter
authors.initials: P
authors.lastname: Nordlander
authors.affiliation: Department of Physics, Chalmers University of Technology , 412 96 Göteborg, Sweden.
authors.forename: Mikael
authors.initials: M
authors.lastname: Käll
keywords: Chiral nanostructures; circular dichroism; dichroic-sensitive cathodoluminescence; hot electron generation; surface plasmons