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Universal Prethermalization in Interacting Bose-Fermi Degenerate Systems

Revista, Zen, PHYSICS, 10

Published Nov 28, 2025• 0 citations

Abstract

This paper explores the phenomenon of universal prethermalization in out-of-equilibrium interacting Bose-Fermi degenerate systems. Prethermalization, a transient non-equilibrium state characterized by a quasi-stationary distribution that is thermal with respect to a restricted set of effective conserved quantities, has emerged as a fundamental concept in the understanding of isolated quantum many-body systems far from equilibrium. We specifically focus on the unique interplay between bosonic and fermionic degrees of freedom, which introduces novel pathways for relaxation and distinct characteristics of prethermal plateaus. The universality of prethermal dynamics, implying independence from microscopic details and initial conditions within certain regimes, is investigated in the context of interspecies interactions, density imbalances, and dimensionality. We review the theoretical frameworks, including mean-field descriptions, effective Hamiltonians, and kinetic equations, alongside experimental observations in ultracold atomic gases that provide a fertile ground for studying such non-equilibrium phenomena. The emergence of universal scaling laws and the role of conservation laws in defining the prethermal state are discussed, paving the way for a deeper understanding of thermalization processes and the persistence of non-equilibrium states in complex quantum matter.

DOI: 10.5281/zenodo.17752360

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