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arXiv · 2410.22604

CaCo$_2$TeO$_6$: A topochemically prepared 3$d^7$ honeycomb Kitaev magnet

Yuya Haraguchi·Yuto Yoshida·Akira Matsuo·Koichi Kindo·Hiroko Aruga Katori
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Abstract

We report the magnetic properties of CaCo$_2$TeO$_6$ as a Kitaev candidate. CaCo$_2$TeO$_6$ was synthesized through a topochemical process, wherein all Na$^+$ ions in Na$_2$Co$_2$TeO$_6$ were replaced with half the amount of Ca$^{2+}$ ions. This substitution brings the CoO$_6$ octahedra closer to an approximate cubic symmetry. CaCo$_2$TeO$_6$ exhibits antiferromagnetic ordering at $T_N \sim 13$ K, which is lower than $\sim$ 27 K observed for Na$_2$Co$_2$TeO$_6$. Notably, its magnetic order is suppressed in a relatively low magnetic field of approximately 4 T, indicating that non-Kitaev interactions can be restrained by reducing trigonal distortion. Our findings highlight the potential of CaCo$_2$TeO$_6$ as a viable platform for exploring Kitaev quantum spin liquids and pave the way for a deeper understanding of the fundamental mechanisms in Kitaev physics.

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Yuya Haraguchi, Yuto Yoshida, Akira Matsuo, Koichi Kindo, Hiroko Aruga Katori. 2024-10-30. CaCo$_2$TeO$_6$: A topochemically prepared 3$d^7$ honeycomb Kitaev magnet. https://doi.org/10.1103/physrevb.110.184411

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