Theoretical description of atomtronic Josephson junctions in an optical lattice

Abstract

Experimental realizations of ``atomtronic" Josephson junctions have recently been created in annular traps in relative rotation with respect to potential barriers that generate the weak links. If these devices are additionally subjected to an optical lattice potential, then they can incorporate strong-coupling Mott physics within the design, which can modify the behavior and can allow for interesting new configurations of barriers and of superfluid flow patterns. We examine theoretically the behavior of a Bose superfluid in an optical lattice in the presence of an annular trap and a barrier across the annular region which acts as a Josephson junction. As the superfluid is rotated, circulating super-currents appear. Beyond a threshold superfluid velocity, phase slips develop, which generate vortices. We use a finite temperature strong-coupling expansion about the mean-field solution of the Bose Hubbard model to calculate various properties of such devices. In addition, we discuss some of the rich behavior that can result when there are Mott regions within the system.

12 pages, 9 figures

References in corpus (17)

• Observation of persistent flow of a Bose-Einstein condensate in a toroidal trap
• Atomtronic circuits: from many-body physics to quantum technologies
• Interferometric measurement of the current-phase relationship of a superfluid weak link
• Coherent superposition of current flows in an Atomtronic Quantum Interference Device
• Strong-coupling expansion for the momentum distribution of the Bose Hubbard model with benchmarking against exact numerical results
• Persistent Currents in Toroidal Dipolar Supersolids
• Vortices in a toroidal Bose-Einstein condensate with a rotating weak link
• Interaction-resistant metals in multicomponent Fermi systems
• Perspective on new implementations of atomtronic circuits
• Superflow decay in a toroidal Bose gas: The effect of quantum and thermal fluctuations
• Superfluidity in Bose-Hubbard circuits
• Temperature-dependent periodicity of the persistent current in strongly interacting systems
• Decay of persistent currents in annular atomic superfluids
• Implementation of an atomtronic SQUID in a strongly confined toroidal condensate
• Superfluidity fraction of few bosons in an annular geometry in the presence of a rotating weak link
• Persistent currents in a strongly interacting multicomponent Bose gas on a ring
• Parametric triggering of vortices in toroidally trapped rotating Bose-Einstein condensates