title: 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° 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 R2Mo2O7.
authors.affiliation: Institute for Theoretical Solid State Physics, IFW Dresden, 01171 Dresden, Germany.
authors.forename: Sanjeev
authors.initials: S
authors.lastname: Kumar
authors.forename: Jeroen
authors.initials: J
authors.lastname: van den Brink