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arXiv · 0807.3552

Scalar spin chirality and quantum Hall effect on a triangular lattice

Ivar Martin·C. D. Batista
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Abstract

We study the Kondo Lattice and Hubbard models on a triangular lattice for band filling factor 3/4. We show that a simple non-coplanar chiral spin ordering (scalar spin chirality) is naturally realized in both models due to perfect nesting of the Fermi surface. The resulting triple-Q magnetic ordering is a natural counterpart of the collinear Neel ordering of the half-filled square lattice Hubbard model. We show that the obtained chiral phase exhibits a spontaneous quantum Hall-effect with sigma_{xy}= e^2/h.

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Ivar Martin, C. D. Batista. 2008-07-23. Scalar spin chirality and quantum Hall effect on a triangular lattice. https://doi.org/10.1103/physrevlett.101.156402

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