Nonequilibrium many-body dynamics along a dissipative Hubbard chain: Symmetries and Quantum Monte Carlo simulations

TL;DR

This paper investigates the nonequilibrium dynamics of correlated charge transfer in a dissipative Hubbard chain, highlighting the role of symmetries, invariant subspaces, and employing advanced Quantum Monte Carlo methods to analyze charge transport.

Contribution

It introduces a detailed symmetry analysis in a dissipative Hubbard model and applies an improved Quantum Monte Carlo approach to study many-body dynamics.

Findings

Time evolution occurs independently in invariant subspaces.

Asymptotic states can be non-Boltzmann equilibrium.

Rate equations effectively describe incoherent regime dynamics.

Abstract

The nonequilibrium dynamics of correlated charge transfer along a one-dimensional chain in presence of a phonon environment is investigated within a dissipative Hubbard model. For this generalization of the ubiquitous spin-boson model the crucial role of symmetries is analysed in detail and corresponding invariant subspaces are identified. It is shown that the time evolution typically occurs in each of the disjunct subspaces independently leading e.g. asymptotically to a non-Boltzmann equilibrium state. Based on these findings explicit results are obtained for two interacting electrons by means of a substantially improved real-time quantum Monte Carlo approach. In the incoherent regime an appropriate mapping of the many-body dynamics onto an isomorphic single particle motion allows for an approximate description of the numerical data in terms of rate equations. These results may lead to new control schemes of charge transport in tailored quantum systems as e.g. molecular chains or quantum dot arrays.