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arXiv · 2402.04197

Functional renormalisation group approach to the finite-temperature Bose polaron

Felipe Isaule
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Abstract

The functional renormalisation group (FRG) approach is employed to study Bose polarons at finite temperatures in the regime of strong attractive bath-impurity interactions. Both two- and three-dimensional configurations are considered. The appearance of two polaron quasiparticle branches at finite temperatures is revealed, consistent with recent findings by other analytical techniques. Ground-state polaron energies are also reported for selected interactions and temperatures within the gas superfluid phase. The findings of this work present the FRG as a useful tool for studying finite-temperature polarons in quantum gases.

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Felipe Isaule. 2024-02-06. Functional renormalisation group approach to the finite-temperature Bose polaron. https://doi.org/10.1209/0295-5075%2Fad763d

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