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Breakdown of the local density approximation in interacting systems of cold fermions in strongly anisotropic traps

Adilet Imambekov·C. J. Bolech·Mikhail Lukin·Eugene Demler
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Abstract

We consider spin-polarized mixtures of cold fermionic atoms on the BEC side of the Feshbach resonance. We demonstrate that a strongly anisotropic confining potential can give rise to a double-peak structure in the axial distribution of the density difference and a polarization-dependent aspect ratio of the minority species. Both phenomena appear as a result of the breakdown of the local density approximation for the phase-separated regime. We speculate on the implications of our findings for the unitary regime.

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Adilet Imambekov, C. J. Bolech, Mikhail Lukin, Eugene Demler. 2006-12-06. Breakdown of the local density approximation in interacting systems of cold fermions in strongly anisotropic traps. https://doi.org/10.1103/physreva.74.053626

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