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arXiv · 1305.6948

Combined topological and Landau order from strong correlations in Chern bands

Stefanos Kourtis·Maria Daghofer
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Abstract

We present a class of states with both topological and conventional Landau order that arise out of strongly interacting spinless fermions in fractionally filled and topologically non-trivial bands with Chern number $C=\pm 1$. These quantum states show the features of fractional Chern insulators, such as fractional Hall conductivity and interchange of ground-state levels upon insertion of a magnetic flux. In addition, they exhibit charge order and a related additional trivial ground-state degeneracy. Band mixing and geometric frustration of the charge pattern place these lattice states markedly beyond a single-band description.

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Stefanos Kourtis, Maria Daghofer. 2014-12-10. Combined topological and Landau order from strong correlations in Chern bands. https://doi.org/10.1103/physrevlett.113.216404

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