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arXiv · 2312.07994

Comment on "Excitation Spectrum and Superfluid Gap of an Ultracold Fermi Gas"

Yvan Castin
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Abstract

We present simple arguments suggesting that H. Biss et al [PRL 128, 100401 (2022)] did not measure with the required accuracy the low-wavenumber curvature of the acoustic excitation branch of the ground-state unitary Fermi gas. This difficult-to-calculate quantity is crucial for the relaxation dynamics of the gas at low temperature.

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Yvan Castin. 2023-12-13. Comment on "Excitation Spectrum and Superfluid Gap of an Ultracold Fermi Gas". https://doi.org/10.1103/physrevlett.133.109301

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