arXiv:cond-mat/0605166 · Physical Review B

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

Lothar Mühlbacher, Joachim Ankerhold

Published Oct 12, 2006• 3 citations

Abstract

The nonequilibrium dynamics of correlated charge transfer along a one-dimensional chain in the 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 analyzed 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 control schemes of charge transport in tailored quantum systems as, e.g., molecular chains or quantum dot arrays.

DOI: 10.1103/physrevb.74.165105

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