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arXiv · 1803.06447

Emergence of spin-orbit order in the spinel CuCr$_2$O$_4$

K. Tomiyasu·S. Lee·H. Ishibashi·Y. Takahashi·T. Kawamata·Y. Koike·T. Nojima·S. Torii·T. Kamiyama
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Abstract

We determined the magnetic structure of CuCr$_2$O$_4$ using neutron diffraction and irreducible representation analysis. The measurements identified a new phase between 155 K and 125 K as nearly collinear magnetic ordering in the Cr pyrochlore lattice. Below 125 K, a Cu-Cr ferrimagnetic component develops the noncollinear order. Along with the simultaneously obtained O positions and the quantum effect of spin-orbit coupling, the magnetic structure is understood to involve spin-orbit ordering, accompanied by an appreciably deformed orbital of presumably spin-only Cu and Cr.

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K. Tomiyasu, S. Lee, H. Ishibashi, Y. Takahashi, T. Kawamata, Y. Koike, T. Nojima, S. Torii, T. Kamiyama. 2018-03-17. Emergence of spin-orbit order in the spinel CuCr$_2$O$_4$. https://arxiv.org/abs/1803.06447

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