title: One-dimensional transport of bosons between weakly linked reservoirs.
abstract: We study a flow of ultracold bosonic atoms through a one-dimensional channel that connects two macroscopic three-dimensional reservoirs of Bose-condensed atoms via weak links implemented as potential barriers between each of the reservoirs and the channel. We consider reservoirs at equal chemical potentials so that a superflow of the quasicondensate through the channel is driven purely by a phase difference 2Φ imprinted between the reservoirs. We find that the superflow never has the standard Josephson form ∼sin2Φ. Instead, the superflow discontinuously flips direction at 2Φ=±π and has metastable branches. We show that these features are robust and not smeared by fluctuations or phase slips. We describe a possible experimental setup for observing these phenomena.
authors.affiliation: School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom.
authors.forename: D P
authors.initials: DP
authors.lastname: Simpson
authors.affiliation: School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom.
authors.forename: D M
authors.initials: DM
authors.lastname: Gangardt
authors.affiliation: School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom.
authors.forename: I V
authors.initials: IV
authors.lastname: Lerner
authors.affiliation: Midlands Ultracold Atom Research Centre, School of Physics and Astronomy, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom.
authors.forename: P
authors.initials: P
authors.lastname: Krüger