We characterize the current-carrying nonequilibrium steady-state in a single-band Hubbard model confronted with a static electric field in the presence of quenched disorder. As disorder is not expected to dissipate the extra energy injected by the field, optical phonons assisted by a fermionic heat bath serve as dissipation channels for the current-induced Joule heat generated by the accelerated electrons. In a purely electronic setup, the disorder-induced dephasing cannot contribute states within the gap but only smear out the edges of the Hubbard bands. When phonons are taken into account, the different nature of disorder-induced dephasing and phonon-related dissipation becomes clear. We show that although both disorder and electron-phonon interaction enhance the current at off-resonant fields, disorder effects play a marginal role since they cannot provide in-gap states which are instead brought about by phonons and represent the privileged relaxation pathway for excited electrons.
@article{arxiv.2310.11833,
title = {Disordered Mott insulators in strong electric fields},
author = {Tommaso Maria Mazzocchi and Daniel Werner and Enrico Arrigoni},
journal= {arXiv preprint arXiv:2310.11833},
year = {2023}
}