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arXiv · 2601.22553

Analysis of self-thermalization dynamics in the Bose-Hubbard model by using the pseudoclassical approach

Andrey R. Kolovsky
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Abstract

We analyze the self-thermalization dynamics of the $M$-site Bose-Hubbard model in terms of the single-particle density matrix that is calculated by using the pseudoclassical approach. It is shown that a weak inter-particle interaction, which suffices to convert the integrable system of non-interacting bosons into a chaotic system, has a negligible effect on the thermal density matrix given by the Bose-Einstein distribution. This opens the door for equilibration where the two coupled Bose-Hubbard systems, which are initially in different thermal states, relax to the same thermal state. When we couple these two subsystems by using a lattice of the length $L\ll M$, we numerically calculate the quasi-stationary current of Bose particles across the lattice and show that its magnitude is consistent with the solution of the master equation for the boundary driven $L$-site Bose-Hubbard model.

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Andrey R. Kolovsky. 2026-01-30. Analysis of self-thermalization dynamics in the Bose-Hubbard model by using the pseudoclassical approach. https://arxiv.org/abs/2601.22553

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