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arXiv · 1207.0402

Photo-induced states in a Mott insulator

Martin Eckstein·Philipp Werner
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Abstract

We investigate the properties of the metallic state obtained by photo-doping carriers into a Mott insulator. In a strongly interacting system, these carriers have a long life-time, so that they can dissipate their kinetic energy to a phonon bath. In the relaxed state, the scattering rate saturates at a non-zero temperature-independent value, and the momentum-resolved spectral function features broad bands which differ from the well-defined quasi-particle bands of a chemically doped system. Our results indicate that a photo-doped Mott insulator behaves as a bad metal, in which strong scattering between doublons and holes inhibits Fermi-liquid behavior down to low temperature.

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Martin Eckstein, Philipp Werner. 2012-07-02. Photo-induced states in a Mott insulator. https://doi.org/10.1103/physrevlett.110.126401

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