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Superfluidity versus Anderson localization in a dilute Bose gas.
T Paul1, P Schlagheck, P Leboeuf
1Laboratoire de Physique Théorique et Modèles Statistiques, CNRS, Université Paris Sud, UMR8626, 91405 Orsay Cedex, France.
Physical Review Letters
|August 7, 2007
Summary
We studied Bose-Einstein condensate beams in disordered areas, finding two flow types: superfluid and localized supersonic flow. The supersonic flow disappears in larger disordered samples.
Area of Science:
- Quantum physics
- Condensed matter physics
Background:
- Bose-Einstein condensates (BECs) exhibit superfluidity.
- Disordered potentials can induce Anderson localization.
Purpose of the Study:
- Investigate the dynamics of quasi-one-dimensional BEC beams in finite disordered regions.
- Analyze the emergence of distinct flow regimes and Anderson localization.
Main Methods:
- Analytical computation of particle motion.
- Modeling of interaction effects in disordered potentials.
Main Results:
- Identified two stationary flow regions: subsonic superfluid flow and supersonic dissipative flow.
- Observed Anderson localization in the supersonic regime.
- Derived the interaction-dependent localization length.
- Explained the vanishing of supersonic flow for large disordered samples.
Conclusions:
- Interaction effects in disordered BECs create complex flow behaviors.
- Anderson localization is a key feature of supersonic flow in these systems.
- The extent of the disordered region significantly influences the observed phenomena.
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