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11:21
Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
Driving phase slips in a superfluid atom circuit with a rotating weak link.
K C Wright1, R B Blakestad, C J Lobb
1National Institute of Standards and Technology and University of Maryland, Gaithersburg, Maryland 20899, USA.
Physical Review Letters
|February 7, 2013
Summary
Researchers observed phase slips in atomic Bose-Einstein condensates, mimicking superconducting behavior. This system allows dynamic control over the current-phase relation, offering new insights into quantum fluid dynamics.
Area of Science:
- Atomic physics
- Quantum fluids
- Condensed matter physics
Background:
- Superconducting loops with weak links exhibit quantized flux states.
- Atomic Bose-Einstein condensates (BECs) provide a tunable quantum fluid system.
- Understanding phase dynamics in superfluids is crucial for quantum technologies.
Purpose of the Study:
- To investigate phase slip phenomena in a toroidal atomic Bose-Einstein condensate.
- To explore the analogy between atomic BECs and superconducting weak links.
- To demonstrate the dynamic control of the current-phase relation in a quantum fluid.
Main Methods:
- Creation of a toroidal atomic (23Na) Bose-Einstein condensate.
- Introduction of a localized weak link by reducing superfluid density.
- Rotation of the weak link around the condensate ring.
- Observation of phase slips and vortex entry.
Main Results:
- Well-defined phase slips were observed between quantized persistent current states.
- Phase slips were induced by slowly rotating the weak link.
- Rapid rotation of the weak link led to vortex entry into the condensate.
- The current-phase relation of the weak link could be dynamically varied.
Conclusions:
- Atomic Bose-Einstein condensates serve as a versatile platform to study phenomena analogous to superconductivity.
- The dynamic control of the current-phase relation in BECs offers advantages over superconducting circuits.
- This work provides new insights into the fundamental physics of phase coherence and dissipation in quantum fluids.
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