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Updated: Mar 29, 2026
11:21
Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
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Hydrodynamic Attractor in Periodically Driven Ultracold Quantum Gases.
Aleksas Mazeliauskas1, Tilman Enss1
1University of Heidelberg, Institute for Theoretical Physics, 69120 Heidelberg, Germany.
Physical Review Letters
|March 27, 2026
Summary
Strongly interacting systems exhibit novel cyclic hydrodynamic attractors under periodic expansion and contraction. This discovery, observed in ultracold quantum gases, offers new experimental avenues for studying these phenomena beyond conventional models.
Area of Science:
- Condensed matter physics
- High-energy nuclear physics
- Quantum gases
Background:
- Hydrodynamic attractors describe system evolution outside conventional hydrodynamics.
- Previous studies focused on monotonic expansion, limiting understanding.
- Explaining applicability in high-energy nuclear collisions is crucial.
Purpose of the Study:
- Investigate hydrodynamic attractors in systems with periodic expansion and contraction.
- Explore cyclic attractor behavior beyond monotonic flow.
- Provide a framework for experimental observation in quantum gases.
Main Methods:
- Utilized Müller-Israel-Stewart theory.
- Modeled a driven ultracold Fermi gas.
- Analyzed system behavior under periodic expansion and contraction.
Main Results:
- Demonstrated novel cyclic attractor behavior in periodically driven systems.
- Showed attractors do not converge to Navier-Stokes dynamics at late times.
- Predicted measurable phenomena in ultracold quantum gases.
Conclusions:
- Cyclic attractors represent a new class of hydrodynamic behavior.
- Experimental verification is feasible in ultracold quantum gases with modulated scattering length.
- This work expands the understanding and discovery of hydrodynamic attractors.
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