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Updated: Aug 12, 2026
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Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
Existence of long-range order for trapped interacting bosons
1Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801-3080, USA.
Physical Review Letters
|January 7, 2003
Summary
Researchers derived an inequality for Bose-condensed states, linking condensate fraction to particle number and curvature. This provides an upper bound for Thomas-Fermi condensate size in experiments.
Area of Science:
- Quantum physics
- Condensed matter physics
Background:
- Bose-condensed states exhibit "long-range" order.
- Understanding condensate properties is crucial for quantum technologies.
Purpose of the Study:
- Derive a novel inequality for "long-range" order in localized Bose-condensed states.
- Relate condensate fraction to physical parameters like particle number and curvature.
- Establish an experimentally testable upper bound for condensate size.
Main Methods:
- Theoretical derivation of a new inequality.
- Application to a specific model: one-dimensional, harmonically trapped dilute Bose condensate.
Main Results:
- An inequality governing "long-range" order was derived.
- The inequality connects condensate fraction, temperature, effective curvature radius, and total particle number.
- An explicit upper bound for the Thomas-Fermi condensate size was determined for the specific case.
Conclusions:
- The derived inequality offers a new theoretical tool for Bose-Einstein condensates.
- The upper bound on condensate size is experimentally verifiable with current technology.
- This research advances the understanding of quantum phenomena in confined Bose gases.
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