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Comment on Nonequilibrium dynamics of superconductivity in the attractive Hubbard model

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 نشر من قبل Emil Yuzbashyan
 تاريخ النشر 2018
  مجال البحث فيزياء
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In a recent preprint [arXiv:1803.04118v2] Chern and Barros report numerical simulations of the mean-field interaction quench dynamics, $U_ito U_f$, of the attractive Hubbard model that confirm our earlier prediction [Europhys. Lett. 85, 20004 (2008), arXiv:0805.2798] of spontaneous eruption of spatial inhomogeneities in the post-quench state with periodically oscillating superconducting order. Chern and Barros attribute this instability with respect to spatial fluctuations to the large magnitude of the final Hubbard coupling $U_f$. We point out that this interpretation is inaccurate and discuss further work necessary to numerically verify the mechanism of the instability and the nature of the steady state.



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