title: Metastable states and macroscopic quantum tunneling in a cold-atom Josephson ring.
abstract: We study macroscopic properties of a system of weakly interacting neutral bosons confined in a ring-shaped potential with a Josephson junction. We derive an effective low energy action for this system and evaluate its properties. In particular, we find that the system possesses a set of metastable current-carrying states and evaluate the rates of transitions between these states due to macroscopic quantum tunneling and thermal activation mechanism. Finally, we discuss signatures of different metastable states in the time-of-flight images and argue that the effect is observable within currently available experimental technique.
authors.affiliation: Theoretical Division (T-4), Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA. solenov@lanl.gov
authors.forename: Dmitry
authors.initials: D
authors.lastname: Solenov
authors.forename: Dmitry
authors.initials: D
authors.lastname: Mozyrsky