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arXiv · 1308.3812

Normal mass density of a superfluid Fermi gas at unitarity

Gordon Baym·C. J. Pethick
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Abstract

We calculate the normal mass density of a paired Fermi gas at unitarity. The dominant contribution near the superfluid transition is from fermionic quasiparticle excitations, and is thus sensitive to the pairing gap. A comparison with the recent experiment of Sidorenkov et al. suggests that the superfluid gap near the transition temperature is larger than the BCS value, but the data do not permit a quantitative inference of the gap. Calculations of the quenched moment of inertia of a BCS superfluid in a harmonic trap are in reasonable agreement with the earlier experiment of Riedl et al.

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Gordon Baym, C. J. Pethick. 2013-10-24. Normal mass density of a superfluid Fermi gas at unitarity. https://doi.org/10.1103/physreva.88.043631

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