Dissipation in a Finite Temperature Atomic Josephson Junction
arXiv:2110.00877 · doi:10.1103/PhysRevResearch.4.033205
Abstract
We numerically demonstrate and characterize the emergence of distinct dynamical regimes of a finite temperature bosonic superfluid in an elongated Josephson junction generated by a thin Gaussian barrier over the entire temperature range where a well-formed condensate can be clearly identified. Although the dissipation arising from the coupling of the superfluid to the dynamical thermal cloud increases with increasing temperature as expected, the importance of this mechanism is found to depend on two physical parameters associated (i) with the initial chemical potential difference, compared to some characteristic value, and (ii) the ratio of the thermal energy to the barrier amplitude. The former determines whether the superfluid Josephson dynamics are dominated by gradually damped plasma-like oscillations (for relatively small initial population imbalances), or whether dissipation at early times is instead dominated by vortex- and sound-induced dissipation (for larger initial imbalances). The latter defines the effect of the thermal cloud on the condensate dynamics, with a reversal of roles, i.e. the condensate being driven by the oscillating thermal cloud, being observed when the thermal particles acquire enough energy to overcome the barrier. Our findings are within current experimental reach in ultracold superfluid junctions.
References in corpus (21)
- Matter-wave interferometry in a double well on an atom chip
- Finite Temperature Models of Bose-Einstein Condensation
- Coherent Oscillations in an Exciton-Polariton Josephson Junction
- Roadmap on Atomtronics: State of the art and perspective
- Josephson junctions with negative second harmonic in the current-phase relation: properties of novel varphi-junctions
- Dynamics of a tunable superfluid junction
- Connecting dissipation and phase slips in a Josephson junction between fermionic superfluids
- Dark soliton dynamics in Bose-Einstein condensates at finite temperature
- The Josephson effect throughout the BCS-BEC crossover
- Tunneling transport of unitary fermions across the superfluid transition
- Vortex reconnections in atomic condensates at finite temperature
- Josephson plasma oscillations and the Gross-Pitaevskii equation: Bogoliubov approach vs two-mode model
- Observable Vortex Properties in Finite Temperature Bose Gases
- Phase-slips and vortex dynamics in Josephson oscillations between Bose-Einstein condensates
- Josephson junction dynamics in a two-dimensional ultracold Bose gas
- Stochastic phase slips in toroidal Bose-Einstein condensates
- Dynamical Phase Diagram of Ultracold Josephson Junctions
- Josephson effect at finite temperature along the BCS-BEC crossover
- Dynamical phase diagram of a one dimensional Bose gas in a box with a tunable weak-link: from Bose-Josephson oscillations to shock waves
- Josephson effect with superfluid fermions in the two-dimensional BCS-BEC crossover
- Phonon-Josephson resonances in atomtronic circuits