Tail-induced equilibration in long-range interacting quantum lattices

Wei-Han Li

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arXiv · 2503.01486

Tail-induced equilibration in long-range interacting quantum lattices

Wei-Han Li

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Abstract

We examine the relation between inter-particle interactions and real-time equilibration in one-dimensional lattice systems with hard-core constraints. Focusing on the roles of interactions, our results demonstrate that in the presence of interaction tails, any power-law exponent (including the limit ones) can encode the random particle configurations to the Hamiltonian, leaving the latter characterized by random matrices. Through an experimental-accessible setup using dipolar-interacting particles in optical lattices, the quenched relaxations are demonstrated resulting in equilibrium, and the relation between eigenstate thermalization is confirmed. Our study directly unveiled the role of inter-particle interactions in quantum many-body dynamics, offering a new scheme to address equilibration in closed quantum many-body problem based on the manifesting of random particle configurations in the model Hamiltonian.

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Wei-Han Li. 2025-03-03. Tail-induced equilibration in long-range interacting quantum lattices. https://arxiv.org/abs/2503.01486

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