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Resistive flow in a weakly interacting Bose-Einstein condensate.
F Jendrzejewski1, S Eckel1, N Murray2
1Joint Quantum Institute, National Institute of Standards and Technology and University of Maryland, Gaithersburg, Maryland 20899, USA.
Physical Review Letters
|August 9, 2014
Summary
Researchers directly observed resistive flow in a Bose-Einstein condensate (BEC). They found a transition from superfluid to resistive flow at a critical weak link velocity, paving the way for advanced atomtronic devices.
Area of Science:
- Quantum physics
- Condensed matter physics
- Atomic physics
Background:
- Bose-Einstein condensates (BECs) are quantum states of matter.
- Superfluidity in BECs allows for frictionless flow.
- Understanding dissipation mechanisms in BECs is crucial for quantum technologies.
Purpose of the Study:
- To directly observe and characterize resistive flow in a weakly interacting atomic BEC.
- To investigate the transition from superfluid to resistive flow.
- To explore the potential for atomtronic devices.
Main Methods:
- Utilized a ring-shaped superfluid atomtronic circuit with two weak links.
- Controlled flow by moving the weak links.
- Measured conductivity in the hydrodynamic limit.
- Compared experimental results with zero-temperature Gross-Pitaevskii simulations and a phenomenological model.
Main Results:
- Direct observation of resistive flow through a weak link in a BEC.
- Identified a critical velocity for the transition from superfluid to resistive flow.
- Measured conductivity four orders of magnitude higher than previously reported for BECs with tunnel junctions.
- Found good agreement between experimental data and theoretical models, highlighting the role of excitations in dissipation.
Conclusions:
- The study elucidates the microscopic origins of dissipation in BECs.
- The findings demonstrate the creation of controlled resistive flow in an atomtronic circuit.
- This research paves the way for the development of more sophisticated atomtronic devices.
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