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Updated: Jul 6, 2026
11:21
Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
Destroying superfluidity by rotating a Fermi gas at unitarity
I Bausmerth1, A Recati, S Stringari
1Dipartimento di Fisica, Università di Trento and CNR-INFM BEC Center, I-38050 Povo, Trento, Italy.
Physical Review Letters
|March 21, 2008
Summary
Rotation induces phase separation in a harmonically trapped Fermi gas at zero temperature, creating a superfluid core and a normal gas layer. This phenomenon is crucial for understanding quantum gas behavior under rotation.
Area of Science:
- Quantum mechanics
- Condensed matter physics
- Ultracold atomic gases
Background:
- Harmonically trapped Fermi gases at zero temperature exhibit superfluid properties.
- Rotation can significantly alter the behavior of quantum systems.
Purpose of the Study:
- To investigate the effects of rotation on a zero-temperature Fermi gas.
- To analyze phase separation and stability in rotating superfluids without vortex formation.
Main Methods:
- Theoretical study of a harmonically trapped Fermi gas.
- Analysis under the assumption of no vortex formation.
- Calculation of superfluid depletion and angular momentum.
Main Results:
- Rotation causes phase separation into a superfluid core and a normal gas layer at unitarity.
- A density discontinuity of n(N)/n(S)=0.85 exists at the interface, independent of rotation speed.
- Superfluid depletion and angular momentum were quantified relative to angular velocity.
Conclusions:
- The study reveals a distinct phase separation mechanism in rotating Fermi gases.
- Stability conditions and critical angular velocity for interface deformation were determined.
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