title: Observation of atomic speckle and Hanbury Brown-Twiss correlations in guided matter waves.
abstract: Speckle patterns produced by multiple independent light sources are a manifestation of the coherence of the light field. Second-order correlations exhibited in phenomena such as photon bunching, termed the Hanbury Brown-Twiss effect, are a measure of quantum coherence. Here we observe for the first time atomic speckle produced by atoms transmitted through an optical waveguide, and link this to second-order correlations of the atomic arrival times. We show that multimode matter-wave guiding, which is directly analogous to multimode light guiding in optical fibres, produces a speckled transverse intensity pattern and atom bunching, whereas single-mode guiding of atoms that are output-coupled from a Bose-Einstein condensate yields a smooth intensity profile and a second-order correlation value of unity. Both first- and second-order coherence are important for applications requiring a fully coherent atomic source, such as squeezed-atom interferometry.
authors.affiliation: ARC Centre of Excellence for Quantum Atom Optics, Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200, Australia.
authors.forename: R G
authors.initials: RG
authors.lastname: Dall
authors.forename: S S
authors.initials: SS
authors.lastname: Hodgman
authors.forename: A G
authors.initials: AG
authors.lastname: Manning
authors.forename: M T
authors.initials: MT
authors.lastname: Johnsson
authors.forename: K G H
authors.initials: KG
authors.lastname: Baldwin
authors.forename: A G
authors.initials: AG
authors.lastname: Truscott
mesh_terms: D006371:Helium / Q000737:chemistry; D007368:Interferometry / Q000379:methods*; D007834:Lasers; D008027:Light; D008956:Models, Chemical; D055095:Optics and Photonics; D017785:Photons
chemical_list: D006371:Helium