Analysis of self-thermalization dynamics in the Bose-Hubbard model by using the pseudoclassical approach
Phys. Rev. A 114, 042204 – Published 8 October, 2026
DOI: https://doi.org/10.1103/73pv-ggpx
Abstract
We analyze the self-thermalization dynamics of the -site Bose-Hubbard model in ring geometry using the single-particle density matrix calculated via the pseudoclassical approach. We show that a weak interparticle interaction, which has a negligible effect on the thermal state given by the Bose-Einstein distribution, suffices to convert the integrable system of noninteracting bosons into a chaotic system. Next, we consider two systems of weakly interacting bosons (i.e., two Bose-Hubbard systems) in different thermal states which are coupled by a point contact. We demonstrate that the chaotic nature of the Bose-Hubbard model ensures irreversible relaxation of both systems to global thermal equilibrium. Finally, substituting the point contact with a lattice of length , we numerically calculate the quasistationary 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 -site Bose-Hubbard system.
