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Updated: May 16, 2026
11:21
Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
Quantum mechanical limitations to spin diffusion in the unitary Fermi gas
Tilman Enss1, Rudolf Haussmann
1Physik Department, Technische Universität München, D-85747 Garching, Germany.
Physical Review Letters
|December 11, 2012
Summary
We calculated spin transport in unitary Fermi gases, finding minimum spin diffusivity and maximum spin drag rates near the quantum diffusion limit. Spin conductivity shows a universal high-frequency tail related to Tan contact density.
Area of Science:
- Quantum physics
- Condensed matter physics
- Ultracold atomic gases
Background:
- Unitary Fermi gas exhibits strongly correlated quantum phenomena.
- Understanding spin transport is crucial for quantum many-body systems.
Purpose of the Study:
- To compute spin transport properties in the unitary Fermi gas.
- To investigate spin diffusivity, spin drag, and spin conductivity.
- To explore the relationship between spin transport and Tan contact.
Main Methods:
- Strong-coupling Luttinger-Ward theory.
- Analysis of frequency-dependent spin conductivity.
- Calculation of spin susceptibility.
Main Results:
- Spin diffusivity reaches a minimum of 1.3 ħ/m in the quantum degenerate regime.
- Spin drag rate maximizes at 1.2k(B)T(F)/ħ.
- Spin conductivity exhibits a universal high-frequency tail proportional to Tan contact density C.
Conclusions:
- Spin transport in unitary Fermi gas is characterized by quantum limits and Tan contact dependence.
- No downturn in spin susceptibility was observed in the normal phase.
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