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arXiv · 1809.04817

Quantum magnetic properties of the spin-1/2 triangular-lattice antiferromagnet Ba$_2$La$_2$CoTe$_2$O$_{12}$

Yuki Kojima·Masari Watanabe·Nobuyuki Kurita·Hidekazu Tanaka·Akira Matsuo·Koichi Kindo·Maxim Avdeev
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Abstract

We report the crystal structure of Ba$_2$La$_2$CoTe$_2$O$_{12}$ determined by Rietveld analysis using X-ray powder diffraction data. It was found from magnetic measurements that Ba$_2$La$_2$CoTe$_2$O$_{12}$ can be described as a spin-1\2 triangular-lattice antiferromagnet with easy-plane anisotropy at low temperatures. This compound undergoes a magnetic phase transition at $T_{\rm N}\,{=}\,3.26$ K to an ordered state with the $120^{\circ}$ structure. The magnetization curve exhibits the one-third plateau characteristic of triangular-lattice quantum antiferromagnets. The antiferromagnetic exchange interaction and the $g$ factors parallel and perpendicular to the $c$ axis were evaluated to be $J/k_{\rm B}\,{=}\,22$ K, $g_{\parallel}\,{=}\,3.5$ and $g_{\perp}\,{=}\,4.5$, respectively.

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Yuki Kojima, Masari Watanabe, Nobuyuki Kurita, Hidekazu Tanaka, Akira Matsuo, Koichi Kindo, Maxim Avdeev. 2018-09-13. Quantum magnetic properties of the spin-1/2 triangular-lattice antiferromagnet Ba$_2$La$_2$CoTe$_2$O$_{12}$. https://doi.org/10.1103/physrevb.98.174406

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