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arXiv · 2004.05014

Emergence of a pseudogap in the BCS-BEC crossover

Adam Richie-Halford·Joaquín E. Drut·Aurel Bulgac
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Abstract

Strongly correlated Fermi systems with pairing interactions become superfluid below a critical temperature $T_c$. The extent to which such pairing correlations alter the behavior of the liquid at temperatures $T > T_c$ is a subtle issue that remains an area of debate, in particular regarding the appearance of the so-called pseudogap in the BCS-BEC crossover of unpolarized spin-$1/2$ nonrelativistic matter. To shed light on this, we extract several quantities of crucial importance at and around the unitary limit, namely: the odd-even staggering of the total energy, the spin susceptibility, the pairing correlation function, the condensate fraction, and the critical temperature $T_c$, using a non-perturbative, constrained-ensemble quantum Monte Carlo algorithm.

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Adam Richie-Halford, Joaquín E. Drut, Aurel Bulgac. 2020-04-10. Emergence of a pseudogap in the BCS-BEC crossover. https://doi.org/10.1103/physrevlett.125.060403

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