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arXiv · 1005.0992

Time-Dependent Mean Field Theory for Quench Dynamics in correlated electron systems

Marco Schiró·Michele Fabrizio
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Abstract

A simple and very flexible variational approach to the out-of-equilibrium quantum dynamics in strongly correlated electron systems is introduced through a time-dependent Gutzwiller wavefunction. As an application, we study the simple case of a sudden change of the interaction in the fermionic Hubbard model and find at the mean field level an extremely rich behaviour. In particular, a dynamical transition between small and large quantum quench regimes is found to occur at half-filling, in accordance with the analysis of Eckstein {\sl et al.}, Phys. Rev. Lett. {\bf 103}, 056403 (2009), obtained by dynamical mean field theory, that turns into a crossover at any finite doping.

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Marco Schiró, Michele Fabrizio. 2010-09-09. Time-Dependent Mean Field Theory for Quench Dynamics in correlated electron systems. https://doi.org/10.1103/physrevlett.105.076401

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