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arXiv · 1007.2278

Frustration-induced insulating chiral spin state in itinerant triangular-lattice magnets

Sanjeev Kumar·Jeroen van den Brink
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Abstract

We study the double-exchange model at half-filling with competing superexchange interactions on a triangular lattice, combining exact diagonalization and Monte-Carlo methods. We find that in between the expected itinerant ferromagnetic and $120^{\circ}$ Yafet-Kittel phases a robust scalar-chiral, insulating spin state emerges. At finite temperatures the ferromagnet - scalar-chiral quantum critical point is characterized by anomalous bad-metal behavior in charge transport as observed in frustrated itinerant magnets R$_2$Mo$_{2}$O$_7$.

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Sanjeev Kumar, Jeroen van den Brink. 2010-11-19. Frustration-induced insulating chiral spin state in itinerant triangular-lattice magnets. https://doi.org/10.1103/physrevlett.105.216405

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