Quantum dynamics of a driven correlated system coupled to phonons.

J. Stefan Institute, SI-1000 Ljubljana, Slovenia.
Physical Review Letters (Impact Factor: 7.73). 12/2011; 107(24):246404. DOI: 10.1103/PhysRevLett.107.246404
Source: PubMed

ABSTRACT Nonequilibrium interplay between charge, spin, and lattice degrees of freedom on a square lattice is studied for a single charge carrier doped in the t-J-Holstein model. In the presence of a static electric field we calculate the quasistationary state. With increasing electron-phonon (e-ph) coupling the carrier mobility decreases; however, we find increased steady state current due to e-ph coupling in the regime of negative differential resistance. We explore the distribution of absorbed energy between the spin and the phonon subsystem. For model parameters as relevant for cuprates, the majority of the gained energy flows into the spin subsystem.

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