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arXiv · 2105.13560

Exploring nonequilibrium phases of photo-doped Mott insulators with Generalized Gibbs ensembles

Yuta Murakami·Shintaro Takayoshi·Tatsuya Kaneko·Zhiyuan Sun·Denis Golež·Andrew J. Millis·Philipp Werner
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Abstract

Photo-excited strongly correlated systems can exhibit intriguing non-thermal phases, but the theoretical investigation of them poses significant challenges. In this work, we introduce a generalized Gibbs ensemble type description for long-lived photo-doped states in Mott insulators. This framework enables systematic studies of photo-induced phases based on equilibrium methods, as demonstrated here for the one-dimensional extended Hubbard model. We determine the nonequilibrium phase diagram, which features $\eta$-pairing and charge density wave phases in a wide doping range, and reveal physical properties of these phases. We show that the peculiar kinematics of photo-doped carriers, and the interaction between them, play an essential role in the formation of the non-thermal phases, and we clarify the differences between photo-doped Mott insulators, chemically-doped Mott insulators and photo-doped semiconductors. Our results demonstrate a new path for the systematic exploration of nonequilibrium strongly correlated systems and show that photo-doped Mott insulators host different phases than conventional semiconductors.

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Yuta Murakami, Shintaro Takayoshi, Tatsuya Kaneko, Zhiyuan Sun, Denis Golež, Andrew J. Millis, Philipp Werner. 2021-05-28. Exploring nonequilibrium phases of photo-doped Mott insulators with Generalized Gibbs ensembles. https://doi.org/10.1038/s42005-021-00799-7

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