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arXiv · 1405.3808

Spontaneous loop-spin current with topological characters in the Hubbard model

Shimpei Goto·Keisuke Masuda·Susumu Kurihara
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Abstract

We find a state characterized by a spontaneous loop-spin current and a single-particle gap in the Hubbard model within the variational cluster approach. This state exists for arbitrarily small interaction in a half-filled honeycomb lattice. Moreover, from the calculations of the topological invariants for the interacting system, it is shown that this gapped state has nontrivial topological characters; this state is the topological Mott insulating state. This result implies the ubiquity of topological Mott insulating phases.

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Shimpei Goto, Keisuke Masuda, Susumu Kurihara. 2014-08-05. Spontaneous loop-spin current with topological characters in the Hubbard model. https://doi.org/10.1103/physrevb.90.075102

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