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arXiv · 2310.11216

Back-reaction and correlation effects on pre-thermalization in Mott-Hubbard systems

Friedemann Queisser·Christian Kohlfürst·Ralf Schützhold
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Abstract

For the Fermi-Hubbard model in the strongly interacting Mott insulator state, we study the pre-thermalization dynamics after a quench. To this end, we employ the method of the hierarchy of correlations and compare different levels of accuracy. To leading order, the usual free quasi-particle dynamics (as encoded in the two-point correlation functions) yields the standard picture of pre-thermalization. Taking into account the back-reaction of these quasi-particle fluctuations onto the mean-field background as the first next-to-leading order effect, we observe a strong degradation of pre-thermalization, especially in low dimensions. In contrast, the inclusion of three-point correlations enhances pre-thermalization.

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Friedemann Queisser, Christian Kohlfürst, Ralf Schützhold. 2023-10-17. Back-reaction and correlation effects on pre-thermalization in Mott-Hubbard systems. https://doi.org/10.1103/physrevb.109.195140

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