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arXiv:2609.05137

Environment-assisted transport in a strongly correlated boundary-driven Fermi-Hubbard chain

Hakan Yeler, Özgür Çakır

cond-mat.str-elquant-phSubmitted Sep 4, 2026• Announced Sep 7, 2026• 0 citations
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Abstract

We study steady-state transport in a one-dimensional Fermi-Hubbard chain coupled to particle reservoirs at the boundaries and to local dephasing baths at each site, using the time-evolving block decimation (TEBD) method to solve the Lindblad master equation. In the absence of dephasing, the current exhibits two well-separated maxima as a function of the boundary driving rate, reflecting the distinct charge and spin energy scales of the strongly correlated regime. Upon introducing dephasing, we find two distinct dephasing-induced transport-enhancement regimes, in contrast to the single enhancement previously reported for spinless fermions. Analysis of the non-equilibrium steady state in the Hamiltonian eigenbasis reveals that the two regimes originate from distinct dephasing-induced redistribution processes: the first involves redistribution within the uppermost Hubbard band, while the second involves transitions between Hubbard bands. Our results demonstrate how many-body correlations shape the interplay between coherent driving, dephasing, and quantum Zeno physics in strongly correlated open systems.

Comments
23 pages, 7 figures

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