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arXiv · 0908.1807

Time-resolved photoemission of correlated electrons driven out of equilibrium

B. Moritz·T. P. Devereaux·J. K. Freericks
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Abstract

We describe the temporal evolution of the time-resolved photoemission response of the spinless Falicov-Kimball model driven out of equilibrium by strong applied fields. The model is one of the few possessing a metal-insulator transition and admitting an exact solution in the time domain. The nonequilibrium dynamics, evaluated using an extension of dynamical mean-field theory, show how the driven system differs from two common viewpoints - a quasiequilibrium system at an elevated effective temperature (the "hot" electron model) or a rapid interaction quench ("melting" of the Mott gap) - due to the rearrangement of electronic states and redistribution of spectral weight. The results demonstrate the inherent trade-off between energy and time resolution accompanying the finite width probe pulses, characteristic of those employed in pump-probe time-domain experiments, which can be used to focus attention on different aspects of the dynamics near the transition.

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B. Moritz, T. P. Devereaux, J. K. Freericks. 2009-08-12. Time-resolved photoemission of correlated electrons driven out of equilibrium. https://doi.org/10.1103/physrevb.81.165112

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