title: Photoassociation of a Bose-Einstein condensate near a Feshbach resonance.
abstract: We measure the effect of a magnetic Feshbach resonance (FR) on the rate and light-induced frequency shift of a photoassociation resonance in ultracold 7Li. The photoassociation-induced loss-rate coefficient K_{p} depends strongly on magnetic field, varying by more than a factor of 10;{4} for fields near the FR. At sufficiently high laser intensities, K_{p} for a thermal gas decreases with increasing intensity, while saturation is observed for the first time in a Bose-Einstein condensate. The frequency shift is also strongly field dependent and exhibits an anomalous blueshift for fields just below the FR.
authors.affiliation: Department of Physics and Astronomy and Rice Quantum Institute, Rice University, Houston, Texas 77251, USA.
authors.forename: M
authors.initials: M
authors.lastname: Junker
authors.forename: D
authors.initials: D
authors.lastname: Dries
authors.forename: C
authors.initials: C
authors.lastname: Welford
authors.forename: J
authors.initials: J
authors.lastname: Hitchcock
authors.forename: Y P
authors.initials: YP
authors.lastname: Chen
authors.forename: R G
authors.initials: RG
authors.lastname: Hulet