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arXiv · 1811.00446

Spin-polarized droplets in the unitary Fermi gas

Piotr Magierski·Buğra Tüzemen·Gabriel Wlazłowski
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Abstract

We demonstrate the existence of a new type of spatially localized excitations in the unitary Fermi gas: spin polarized droplets with a peculiar internal structure involving the abrupt change of the pairing phase at the surface of the droplet. It resembles the structure of the Josephson-$π$ junction occurring when a slice of a ferromagnet is sandwiched between two superconductors. The stability of the impurity is enhanced by the mutual interplay between the polarization effects and the pairing field, resulting in an exceptionally long-lived state. The prospects for its realization in experiment are discussed.

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Piotr Magierski, Buğra Tüzemen, Gabriel Wlazłowski. 2019-09-17. Spin-polarized droplets in the unitary Fermi gas. https://doi.org/10.1103/physreva.100.033613

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