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arXiv · 0907.0945

Photoinduced insulator-metal transition and nonlinear optical response of correlated electrons -- a DMFT analysis

Naoto Tsuji·Takashi Oka·Hideo Aoki
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Abstract

We investigate a photoinduced insulator-metal transition in the Falicov-Kimball model with the dynamical mean-field theory (DMFT) extended to nonequilibrium systems in periodic modulations in time. When the photon energy of the pump light is $\Omega \approx U$ ($U$: the interaction strength), a Drude-like peak is found to grow in the optical conductivity spectrum, which is an evidence that the system is driven into a metallic state. During the transition, the band gap does not collapse, whereas the distribution function exhibits a non-monotonic behaviour away from the Fermi distribution. This indicates that the transition cannot be accounted for by heating effects, but creation of photo-carriers is responsible.

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Naoto Tsuji, Takashi Oka, Hideo Aoki. 2009-07-06. Photoinduced insulator-metal transition and nonlinear optical response of correlated electrons -- a DMFT analysis. https://doi.org/10.1088/1742-6596/148/1/012058

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