Pair correlations in the normal phase of an attractive Fermi gas

M. Pini; P. Pieri; M. Jäger; J. Hecker Denschlag; G. Calvanese Strinati

doi:10.1088/1367-2630/ab9ee3

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arXiv · 1912.04802

Pair correlations in the normal phase of an attractive Fermi gas

M. Pini·P. Pieri·M. Jäger·J. Hecker Denschlag·G. Calvanese Strinati

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Abstract

In a recent paper [Phys. Rev. A 99, 053617 (2019)], the total number of fermion pairs in a spin-balanced two-component Fermi gas of $^6$Li atoms was experimentally probed in the normal phase above the superfluid critical temperature, in order to investigate the sectors of pseudogap and preformed-pair in the temperature-coupling phase diagram. Here, we present a theoretical account of these experimental results in terms of an ab-initio self-consistent $t$-matrix calculation, which emphasizes the role of the pair-correlation function between opposite-spin fermions at equilibrium. Good agreement is found between the available experimental data and the theoretical results obtained with no adjustable parameter.

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M. Pini, P. Pieri, M. Jäger, J. Hecker Denschlag, G. Calvanese Strinati. 2019-12-10. Pair correlations in the normal phase of an attractive Fermi gas. https://doi.org/10.1088/1367-2630/ab9ee3

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