title: Classical bifurcation at the transition from Rabi to Josephson dynamics.
abstract: We report on the experimental demonstration of the internal bosonic Josephson effect in a rubidium spinor Bose-Einstein condensate. The measurement of the full time dynamics in phase space allows the characterization of the theoretically predicted π-phase modes and quantitatively confirms analytical predictions, revealing a classical bifurcation. Our results suggest that this system is a model system which can be tuned from classical to the quantum regime and thus is an important step towards the experimental investigation of entanglement generation close to critical points.
authors.affiliation: Kirchhoff Institut für Physik, Universität Heidelberg, Im Neuenheimer Feld 227, D-69120, Germany.
authors.forename: Tilman
authors.initials: T
authors.lastname: Zibold
authors.forename: Eike
authors.initials: E
authors.lastname: Nicklas
authors.forename: Christian
authors.initials: C
authors.lastname: Gross
authors.forename: Markus K
authors.initials: MK
authors.lastname: Oberthaler