title: Effect of light assisted collisions on matter wave coherence in superradiant Bose-Einstein condensates.
abstract: We investigate experimentally the effects of light assisted collisions on the coherence between momentum states in Bose-Einstein condensates. The onset of superradiant Rayleigh scattering serves as a sensitive monitor for matter-wave coherence. A subtle interplay of binary and collective effects leads to a profound asymmetry between the two sides of the atomic resonance and provides far bigger coherence loss rates for a condensate bathed in blue detuned light than previously estimated. We present a simplified quantitative model containing the essential physics to explain our experimental data and point at a new experimental route to study strongly coupled light matter systems.
authors.affiliation: Niels Bohr Institute, Danish Quantum Optics Center QUANTOP, Copenhagen University, Denmark. nir.kampel@nbi.dk
authors.forename: N S
authors.initials: NS
authors.lastname: Kampel
authors.forename: A
authors.initials: A
authors.lastname: Griesmaier
authors.forename: M P
authors.initials: MP
authors.lastname: Hornbak Steenstrup
authors.forename: F
authors.initials: F
authors.lastname: Kaminski
authors.forename: E S
authors.initials: ES
authors.lastname: Polzik
authors.forename: J H
authors.initials: JH
authors.lastname: Müller