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arXiv · 2004.13325

Lone octupole and bulk magnetism in osmate 5d2 double perovskites

S. W. Lovesey·D. D. Khalyavin
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Abstract

Cubic double perovskites that host heavy ions with total angular momentum J = 2 can exhibit a singular magnetic state epitomized by a lone octupole and bulk ferro-type magnetism. It exists in the Chen - Balents Hamiltonian with a quadrupole interaction and competing exchange forces between the ions. Our symmetry inspired analysis mirrors the Dzyaloshinskii - Man'ko theory of latent antiferromagnetic ordering, and a 3-k collinear structure. Experimental tests of the singular state include neutron and x-ray Bragg diffraction.

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S. W. Lovesey, D. D. Khalyavin. 2020-04-28. Lone octupole and bulk magnetism in osmate 5d2 double perovskites. https://doi.org/10.1103/physrevb.102.064407

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