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arXiv · 0804.1035

Vortex core states in superfluid Fermi-Fermi mixtures with unequal masses

M. Iskin
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Abstract

We analyze the vortex core states of two-species (mass imbalanced) superfluid fermion mixtures as a function of two-body binding energy in two dimensions. In particular we solve the Bogoliubov-de Gennes equations for a population balanced mixture of $^{6}$Li and $^{40}$K atoms at zero temperature. We find that the vortex core is mostly occupied by the light-mass ($^{6}$Li) fermions and that the core density of the heavy-mass ($^{40}$K) fermions is highly depleted. This is in contrast with the one-species (mass balanced) mixtures with balanced populations where an equal amount of density depletion is found at the vortex core for both pseudospin components.

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M. Iskin. 2008-04-07. Vortex core states in superfluid Fermi-Fermi mixtures with unequal masses. https://doi.org/10.1103/physreva.78.021604

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