title: Magnetic light-matter interactions in a photonic crystal nanocavity.
abstract: We study the magnetic coupling between a metal-coated near-field probe and a photonic crystal nanocavity. The resonance of the nanocavity shifts to shorter wavelengths when the ringlike apex of the probe is above an antinode of the magnetic field of the cavity. We show that this can be attributed to a magnetic light-matter interaction and is in fact a manifestation of Lenz's law at optical frequencies. We use these measurements to determine the magnetic polarizability of the apex of the probe and find good agreement with theory. We discuss how this method could be applied to study the electric and magnetic polarizibilities of nano-objects.
authors.affiliation: Center for Nanophotonics, FOM Institute for Atomic and Molecular Physics (AMOLF), Science Park 104, 1098 XG Amsterdam, The Netherlands. burresi@amolf.nl
authors.forename: M
authors.initials: M
authors.lastname: Burresi
authors.forename: T
authors.initials: T
authors.lastname: Kampfrath
authors.forename: D
authors.initials: D
authors.lastname: van Oosten
authors.forename: J C
authors.initials: JC
authors.lastname: Prangsma
authors.forename: B S
authors.initials: BS
authors.lastname: Song
authors.forename: S
authors.initials: S
authors.lastname: Noda
authors.forename: L
authors.initials: L
authors.lastname: Kuipers