title: Observation of vortex phase singularities in Bose-Einstein condensates.
abstract: We have observed phase singularities due to vortex excitation in Bose-Einstein condensates. Vortices were created by moving a laser beam through a condensate. They were observed as dislocations in the interference fringes formed by the stirred condensate and a second unperturbed condensate. The velocity dependence for vortex excitation and the time scale for re-establishing a uniform phase across the condensate were determined.
authors.affiliation: Department of Physics, Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: S
authors.initials: S
authors.lastname: Inouye
authors.forename: S
authors.initials: S
authors.lastname: Gupta
authors.forename: T
authors.initials: T
authors.lastname: Rosenband
authors.forename: A P
authors.initials: AP
authors.lastname: Chikkatur
authors.forename: A
authors.initials: A
authors.lastname: Görlitz
authors.forename: T L
authors.initials: TL
authors.lastname: Gustavson
authors.forename: A E
authors.initials: AE
authors.lastname: Leanhardt
authors.forename: D E
authors.initials: DE
authors.lastname: Pritchard
authors.forename: W
authors.initials: W
authors.lastname: Ketterle