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arXiv · 1111.6347

Noncollinear magnetism and spin-orbit coupling in 5d pyrochlore oxide Cd2Os2O7

Hiroshi Shinaoka·Takashi Miyake·Shoji Ishibashi
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Abstract

We investigated the electronic and magnetic properties of the pyrochlore oxide Cd$_2$Os$_2$O$_7$ using the density-functional theory plus on-site repulsion ($U$) method, and depict the ground-state phase diagram with respect to $U$. We conclude that the all-in/all-out non-collinear magnetic order is stable in a wide range of $U$. We also show that the easy-axis anisotropy arising from the spin-orbit (SO) coupling plays a significant role in stabilizing the all-in/all-out magnetic order. A \textit{pseudo gap} was observed near the transition between the antiferromagnetic metallic and insulating phases. Finally, we discuss possible origins of the peculiar low-temperature($T$) properties observed in experiments.

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Hiroshi Shinaoka, Takashi Miyake, Shoji Ishibashi. 2011-11-28. Noncollinear magnetism and spin-orbit coupling in 5d pyrochlore oxide Cd2Os2O7. https://doi.org/10.1103/physrevlett.108.247204

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