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arXiv:2511.02618 · Physical Review Research

Post-quench relaxation dynamics of Gross-Neveu lattice fermions

Domenico Giuliano, Reinhold Egger, Bidyut Dey, Andrea Nava

cond-mat.stat-mechcond-mat.quant-gasquant-phSubmitted Nov 4, 2025• Announced Nov 5, 2025• 0 citations
v1 · Nov 4, 2025v2 · Apr 6, 2026
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Abstract

We study the quantum relaxation dynamics for a lattice version of the one-dimensional (1D) $N$-flavor Gross-Neveu (GN) model after a Hamiltonian parameter quench. Allowing for a system-reservoir coupling $γ$, we numerically describe the system dynamics through a time-dependent self-consistent Lindblad master equation. For a closed ($γ=0$) finite-size system subjected to an interaction parameter quench, the order parameter dynamics exhibits oscillations and revivals. In the thermodynamic limit, our results imply that the order parameter reaches its post-quench stationary value in accordance with the eigenstate thermalization hypothesis (ETH). However, time-dependent finite-momentum correlation matrix elements equilibrate only if $γ>0$. Our findings highlight subtle yet important aspects of the post-quench relaxation dynamics of quantum many-body systems.

Journal reference
Phys. Rev. Research 8, 023108 (2026)
DOI
10.1103/qh7t-jsjm
Comments
13 pages, 10 figures

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