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arXiv · 0907.1027

Photoinduced insulator-metal transition in correlated electrons -- a Floquet analysis with the dynamical mean-field theory

Naoto Tsuji·Takashi Oka·Hideo Aoki
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Abstract

In order to investigate photoinduced insulator-metal transitions observed in correlated electron systems, we propose a new theoretical method, where we combine a Floquet-matrix method for AC-driven systems with the dynamical mean-field theory. The method can treat nonequilibrium steady states exactly beyond the linear-response regime. We have applied the method to the Falicov-Kimball model coupled to AC electric fields, and numerically obtained the spectral function, the nonequilibrium distribution function and the current-voltage characteristic. The results show that intense AC fields indeed drive Mott-like insulating states into photoinduced metallic states in a nonlinear way.

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Naoto Tsuji, Takashi Oka, Hideo Aoki. 2009-07-06. Photoinduced insulator-metal transition in correlated electrons -- a Floquet analysis with the dynamical mean-field theory. https://doi.org/10.1088/1742-6596/150/4/042216

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