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arXiv · 1703.10390

Behavior of the impurity atom in a weakly-interacting Bose gas

G. Panochko·V. Pastukhov·I. Vakarchuk
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Abstract

We studied the properties of a single impurity atom immersed in a dilute Bose condensate at low temperatures. In particular, we perturbatively obtained the momentum dependence of the impurity spectrum and damping. By means of the Brillouin-Wigner perturbation theory we also calculated the self-energy both for attractive and repulsive polaron in the long-wavelength limit. The stability problem of the impurity atom in a weakly-interacting Bose gas is also examined.

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G. Panochko, V. Pastukhov, I. Vakarchuk. 2017-03-30. Behavior of the impurity atom in a weakly-interacting Bose gas. https://doi.org/10.5488/cmp.20.13604

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