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arXiv · 1408.1795

First order dynamical phase transitions

Elena Canovi·Philipp Werner·Martin Eckstein
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Abstract

Recently, dynamical phase transitions have been identified based on the non-analytic behavior of the Loschmidt echo in the thermodynamic limit [Heyl et al., Phys.~Rev.~Lett.~{\bf 110}, 135704 (2013)]. By introducing conditional probability amplitudes, we show how dynamical phase transitions can be further classified, both mathematically, and potentially in experiment. This leads to the definition of first-order dynamical phase transitions. Furthermore, we develop a generalized Keldysh formalism which allows to use nonequilibrium dynamical mean-field theory to study the Loschmidt echo and dynamical phase transitions in high-dimensional, non-integrable models. We find dynamical phase transitions of first order in the Falicov-Kimball model and in the Hubbard model.

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Elena Canovi, Philipp Werner, Martin Eckstein. 2015-01-08. First order dynamical phase transitions. https://doi.org/10.1103/physrevlett.113.265702

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