"Temporal response of nonequilibrium correlated electrons"

B. Moritz: T.P. Devereaux, J.K. Freericks; Computer Physics Communications, 01/15/11.

Additional Authors: T.P. Devereaux, J.K. Freericks

Abstract:

In this work we examine the time-resolved, instantaneous current response for the spinless Falicov–Kimball model at half-filling, on both sides of the Mott–Hubbard metal-insulator transition, driven by a strong electric field pump pulse. The results are obtained using an exact, nonequilibrium, many-body impurity solution specifically designed to treat the out-of-equilibrium evolution of electrons in time-dependent fields. We provide a brief introduction to the method and its computational details. We find that the current develops Bloch oscillations, similar to the case of DC driving fields, with an additional amplitude modulation, characterized by beats and induced by correlation effects. Correlations primarily manifest themselves through an overall reduction in magnitude and shift in the onset time of the current response with increasing interaction strength.