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Ferromagnetism in the Mott insulator Ba2NaOsO6

A. S. Erickson·S. Misra·G. J. Miller·R. R. Gupta·Z. Schlesinger·W. A. Harrison·J. M. Kim·I. R. Fisher
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Abstract

Results are presented of single crystal structural, thermodynamic, and reflectivity measurements of the double-perovskite Ba2NaOsO6. These characterize the material as a 5d^1 ferromagnetic Mott insulator with an ordered moment of ~0.2 Bohr magnetons per formula unit and TC = 6.8(3) K. The magnetic entropy associated with this phase transition is close to Rln2, indicating that the quartet groundstate anticipated from consideration of the crystal structure is split, consistent with a scenario in which the ferromagnetism is associated with orbital ordering.

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A. S. Erickson, S. Misra, G. J. Miller, R. R. Gupta, Z. Schlesinger, W. A. Harrison, J. M. Kim, I. R. Fisher. 2007-05-07. Ferromagnetism in the Mott insulator Ba2NaOsO6. https://doi.org/10.1103/physrevlett.99.016404

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