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

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${}_7$.

4+ pages, published version

References in corpus (5)

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