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arXiv · 1012.3827

Spin Drag in Ultracold Fermi Mixtures with Repulsive Interactions

R. A. Duine·Marco Polini·Arnaud Raoux·H. T. C. Stoof·G. Vignale
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Abstract

We calculate the spin-drag relaxation rate for a two-component ultracold atomic Fermi gas with positive scattering length between the two spin components. In one dimension we find that it vanishes linearly with temperature. In three dimensions the spin-drag relaxation rate vanishes quadratically with temperature for sufficiently weak interactions. This quadratic temperature dependence is present, up to logarithmic corrections, in the two-dimensional case as well. For stronger interaction the system exhibits a Stoner ferromagnetic phase transition in two and three dimensions. We show that the spin-drag relaxation rate is enhanced by spin fluctuations as the temperature approaches the critical temperature of this transition from above.

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R. A. Duine, Marco Polini, Arnaud Raoux, H. T. C. Stoof, G. Vignale. 2010-12-17. Spin Drag in Ultracold Fermi Mixtures with Repulsive Interactions. https://doi.org/10.1088/1367-2630%2F13%2F4%2F045010

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