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arXiv · 1108.3066

Spin superstructure and noncoplanar ordering in metallic pyrochlore magnets with degenerate orbitals

Gia-Wei Chern·Cristian D. Batista
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Abstract

We study double-exchange models with itinerant t2g electrons in spinel and pyrochlore crystals. In both cases the localized spins form a network of corner-sharing tetrahedra. We show that the strong directional dependence of t2g orbitals leads to unusual Fermi surfaces that induce spin superstructures and noncoplanar orderings for a weak coupling between itinerant electrons and localized spins. Implications of our results to ZnV2O4 and Cd2Os2O7 are also discussed.

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Gia-Wei Chern, Cristian D. Batista. 2011-08-15. Spin superstructure and noncoplanar ordering in metallic pyrochlore magnets with degenerate orbitals. https://doi.org/10.1103/physrevlett.107.186403

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