title: Preparation of a pure molecular quantum gas.
abstract: An ultracold molecular quantum gas is created by application of a magnetic field sweep across a Feshbach resonance to a Bose-Einstein condensate of cesium atoms. The ability to separate the molecules from the atoms permits direct imaging of the pure molecular sample. Magnetic levitation enables study of the dynamics of the ensemble on extended time scales. We measured ultralow expansion energies in the range of a few nanokelvin for a sample of 3000 molecules. Our observations are consistent with the presence of a macroscopic molecular matter wave.
authors.affiliation: Institut für Experimentalphysik, Universität Innsbruck, Technikerstrabetae 25, 6020 Innsbruck, Austria.
authors.forename: Jens
authors.initials: J
authors.lastname: Herbig
authors.forename: Tobias
authors.initials: T
authors.lastname: Kraemer
authors.forename: Michael
authors.initials: M
authors.lastname: Mark
authors.forename: Tino
authors.initials: T
authors.lastname: Weber
authors.forename: Cheng
authors.initials: C
authors.lastname: Chin
authors.forename: Hanns-Christoph
authors.initials: HC
authors.lastname: Nägerl
authors.forename: Rudolf
authors.initials: R
authors.lastname: Grimm