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arXiv · 2111.07095

Polaron in almost ideal molecular Bose-Einstein condensate

O. Hryhorchak·V. Pastukhov
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Abstract

We discuss properties of a single impurity atom immersed in the spin-$1/2$ dilute Fermi gas with equal populations of two species in the deep Bose-Einstein condensate (BEC) phase. In this limit, when an almost undepleted BEC of the tightly bound molecules of spin-up and spin-down fermions is formed, we calculate the parameters of an impurity spectrum. It is justified that the leading-order contribution to the impurity energy, while being determined by the two- and three-body scattering processes, is dominated by the former ones.

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O. Hryhorchak, V. Pastukhov. 2021-11-13. Polaron in almost ideal molecular Bose-Einstein condensate. https://arxiv.org/abs/2111.07095

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