title: Near-field probing of slow Bloch modes on photonic crystals with a nanoantenna.
abstract: We study the near-field probing of the slow Bloch laser mode of a photonic crystal by a bowtie nano-aperture (BNA) positioned at the end of a metal-coated fiber probe. We show that the BNA acts as a polarizing nanoprobe allowing us to extract information about the polarization of the near-field of the slow-light mode, without causing any significant perturbation of the lasing process. Near-field experiments reveal a spatial resolution better than λ/20 and a polarization ratio as strong as 110. We also demonstrate that the collection efficiency is two orders of magnitude larger for the BNA than for a 200 nm large circular aperture opened at the apex of the same metal-coated fiber tip. The BNA allows for overcoming one of the main limitations of SNOM linked to the well-known trade off between resolution and signal-to-noise ratio.
authors.affiliation: Université de Lyon, Institut des nanotechnologies de Lyon INL-UMR 5270, CNRS, Ecole Centrale de Lyon, Avenue Guy de Collongue, F-69134 Cedex, France.
authors.forename: T-P
authors.initials: TP
authors.lastname: Vo
authors.forename: M
authors.initials: M
authors.lastname: Mivelle
authors.forename: S
authors.initials: S
authors.lastname: Callard
authors.forename: A
authors.initials: A
authors.lastname: Rahmani
authors.forename: F
authors.initials: F
authors.lastname: Baida
authors.forename: D
authors.initials: D
authors.lastname: Charraut
authors.forename: A
authors.initials: A
authors.lastname: Belarouci
authors.forename: D
authors.initials: D
authors.lastname: Nedeljkovic
authors.forename: C
authors.initials: C
authors.lastname: Seassal
authors.forename: G W
authors.initials: GW
authors.lastname: Burr
authors.forename: T
authors.initials: T
authors.lastname: Grosjean