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arXiv · 1507.02818

Critical region of the superfluid transition in the BCS-BEC crossover

T. Debelhoir·N. Dupuis
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Abstract

We determine the size of the critical region of the superfluid transition in the BCS-BEC crossover of a three-dimensional fermion gas, using a renormalization-group approach to a bosonic theory of pairing fluctuations. For the unitary Fermi gas, we find a sizable critical region $[T_G^-,T_G^+]$, of order $T_c$, around the transition temperature $T_c$ with a pronounced asymmetry: $|T_G^+-T_c|/|T_G^--T_c|\sim8$. The critical region is strongly suppressed on the BCS side of the crossover but remains important on the BEC side.

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T. Debelhoir, N. Dupuis. 2016-03-07. Critical region of the superfluid transition in the BCS-BEC crossover. https://doi.org/10.1103/physreva.93.023642

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