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arXiv · 1005.2366

Competition between pairing and ferromagnetic instabilities in ultracold Fermi gases near Feshbach resonances

David Pekker·Mehrtash Babadi·Rajdeep Sensarma·Nikolaj Zinner·Lode Pollet·Martin W. Zwierlein·Eugene Demler
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Abstract

We study the quench dynamics of a two-component ultracold Fermi gas from the weak into the strong interaction regime, where the short time dynamics are governed by the exponential growth rate of unstable collective modes. We obtain an effective interaction that takes into account both Pauli blocking and the energy dependence of the scattering amplitude near a Feshbach resonance. Using this interaction we analyze the competing instabilities towards Stoner ferromagnetism and pairing.

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David Pekker, Mehrtash Babadi, Rajdeep Sensarma, Nikolaj Zinner, Lode Pollet, Martin W. Zwierlein, Eugene Demler. 2010-05-13. Competition between pairing and ferromagnetic instabilities in ultracold Fermi gases near Feshbach resonances. https://doi.org/10.1103/physrevlett.106.050402

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