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arXiv · 1404.6598

Doublon Dynamics of the Hubbard Model on Triangular Lattice

Toshihiro Sato·Hirokazu Tsunetsugu
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Abstract

We study the dynamics of doublon in the half-filled Hubbard model on the triangular lattice by using the cellular dynamical mean field theory. Investigating the nearest-neighbor dynamical correlations, we demonstrate that a nearest-neighbor doublon-holon pair shows a strong attraction, in particular in the insulating phase. We also calculate the on-site dynamical correlation of doublon and find that the life time of doublon is longer in the metallic phase than in the insulating phase. In the long-time region, the metallic phase has persistent fluctuations in various nearest-neighbor configurations, while the fluctuations are vanishingly small in the insulating phase. Obtained results indicate clear differences of dynamics of doublon between in the metallic and in the insulating phases.

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Toshihiro Sato, Hirokazu Tsunetsugu. 2014-04-26. Doublon Dynamics of the Hubbard Model on Triangular Lattice. https://doi.org/10.1103/physrevb.90.115114

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