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arXiv · 1902.01825

Long-range magnetic ordering in rocksalt-type high-entropy oxides

Marco Polo Jimenez-Segura·Tomohiro Takayama·David Bérardan·Andreas Hoser·Manfred Reehuis·Hidenori Takagi·Nita Dragoe
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Abstract

We report the magnetic properties of Mg$_{0.2}$Co$_{0.2}$Ni$_{0.2}$Cu$_{0.2}$Zn$_{0.2}$O, a high-entropy oxide with rocksalt structure, and the influence of substitutions on these properties. From the magnetic susceptibility and neutron diffraction measurements, we found that this compound exhibits long-range magnetic order below 120 K despite the substantial structuraldisorder. The other rocksalt-type high-entropy oxides with various chemical substitutions were found to host either an antiferromagnetic order or spin-glass state depending on the amount of magnetic ions. The presence of magnetic order for such a disordered material potentially provide a route to explore novel magnetic properties and functions.

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Marco Polo Jimenez-Segura, Tomohiro Takayama, David Bérardan, Andreas Hoser, Manfred Reehuis, Hidenori Takagi, Nita Dragoe. 2019-02-05. Long-range magnetic ordering in rocksalt-type high-entropy oxides. https://arxiv.org/abs/1902.01825

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