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arXiv · 2007.05063

Systematic large flavor fTWA approach to interaction quenches in the Hubbard model

Alexander Osterkorn·Stefan Kehrein
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Abstract

We study the nonequilibrium dynamics after an interaction quench in the two-dimensional Hubbard model using the recently introduced fermionic truncated Wigner approximation (fTWA). To assess the range of validity of the method in a systematic way, we consider the SU($N$) Hubbard model with the fermion degeneracy $N$ as a natural semiclassical expansion parameter. Using both a numerical and a perturbative analytical approach we show that fTWA is exact at least up to and including the prethermalization dynamics. We discuss the limitations of the method beyond this regime.

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Alexander Osterkorn, Stefan Kehrein. 2020-07-09. Systematic large flavor fTWA approach to interaction quenches in the Hubbard model. https://doi.org/10.1088/1751-8121/ad6f7a

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