title: Steering Bose-Einstein condensates despite time symmetry.
abstract: A Bose-Einstein condensate in an oscillating spatially asymmetric potential is shown to exhibit a directed current for unbiased initial conditions despite time symmetry. This phenomenon occurs only if the interaction between atoms, treated in mean-field approximation, exceeds a critical value. Our findings can be described with a three-mode model. These three-mode model results corroborate well with a many-body study over a time scale which increases with increasing atom number. The duration of this time scale probes the validity of the used mean-field approximation.
authors.affiliation: Department of Physics and Centre for Computational Science and Engineering, National University of Singapore, Singapore 117542, Republic of Singapore.
authors.forename: Dario
authors.initials: D
authors.lastname: Poletti
authors.forename: Giuliano
authors.initials: G
authors.lastname: Benenti
authors.forename: Giulio
authors.initials: G
authors.lastname: Casati
authors.forename: Peter
authors.initials: P
authors.lastname: Hänggi
authors.forename: Baowen
authors.initials: B
authors.lastname: Li