Quantum Dynamics of a Driven Correlated System Coupled to Phonons

J. Stefan Institute, SI-1000 Ljubljana, Slovenia.
Physical Review Letters (Impact Factor: 7.51). 12/2011; 107(24):246404. DOI: 10.1103/PhysRevLett.107.246404
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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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    • ". Recent microscopic calculations within the driven t-J-Holstein model suggest that, under certain conditions, rapid energy transfer to spin degrees of freedom can occur [32], but considering the relaxation dynamics, only the relaxation of a highly excited charge carrier through Holstein phonons has been investigated thus far [33]. A detailed discussion of the assignment of Γ 1 to the EPI and the choice of the proportionality constant B is given in the Supplemental Material [16]. "
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