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BCS superfluidity in ultracold gases with unequal atomic populations

R. Combescot
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Abstract

We consider the existence of a BCS superfluid phase in $^{6}$Li due to the pairing of two hyperfine states with unequal number of atoms. We show that the domain of existence for this phase will be increased to a very large extent in the vicinity of the threshold for collapse. This is due to the presence of a new phase with anisotropic order parameter. This phase is induced by the anisotropic part of the scattering, linked to the indirect interaction between atoms through density fluctuation exchange.

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R. Combescot. 2000-07-11. BCS superfluidity in ultracold gases with unequal atomic populations. https://doi.org/10.1209/epl%2Fi2001-00394-5

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