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arXiv · 1402.5787

Localized in-gap state in a single electron doped Mott insulator

Weng-Hang Leong·Shun-Li Yu·T. Xiang·Jian-Xin Li
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Abstract

Motivated by the recent atomic-scale scanning tunneling microscope (STM) observation for a spatially localized in-gap state in an electron doped Mott insulator, we evaluate the local electronic state of the Hubbard model on the square lattice using the cluster perturbation theory. An in-gap state is found to exist below the upper Hubbard band around the dopant lattice site, which is consistent with the STM measurements. The emergence of this local in-gap state is accompanied with a rapid reduction of the double occupancy of electrons. A similar in-gap state is also found to exist on the triangular lattice. These results suggest that the in-gap state is an inherent feature of Mott insulators independent of the lattice structure.

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Weng-Hang Leong, Shun-Li Yu, T. Xiang, Jian-Xin Li. 2014-02-24. Localized in-gap state in a single electron doped Mott insulator. https://doi.org/10.1103/physrevb.90.245102

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