Breakdown of the Fermi polaron description near Fermi degeneracy at unitarity

Brendan C. Mulkerin; Xia-Ji Liu; Hui Hu

doi:10.1016/j.aop.2019.04.018

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arXiv · 1808.07671

Breakdown of the Fermi polaron description near Fermi degeneracy at unitarity

Brendan C. Mulkerin·Xia-Ji Liu·Hui Hu

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Abstract

We theoretically investigate attractive Fermi polarons in three dimensions at finite temperature and impurity concentration through the many-body T-matrix theory and high-temperature virial expansion. By using the analytically continued impurity Green's function, we calculate the direct rf spectroscopy of attractive polarons in the unitary regime. Taking the peak value of the rf spectroscopy as the polaron energy and the full width half maximum as the polaron lifetime, we determine the temperature range of validity for the quasi-particle description of Fermi polarons in the unitary limit.

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Brendan C. Mulkerin, Xia-Ji Liu, Hui Hu. 2020-03-11. Breakdown of the Fermi polaron description near Fermi degeneracy at unitarity. https://doi.org/10.1016/j.aop.2019.04.018

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