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arXiv · 1812.05619

Magnetic interactions in the $S = 1/2$ square-lattice antiferromagnets Ba$_2$CuTeO$_6$ and Ba$_2$CuWO$_6$: parent phases of a possible spin liquid

O. Mustonen·S. Vasala·H. Mutch·C. I. Thomas·G. B. G. Stenning·E. Baggio-Saitovitch·E. J. Cussen·M. Karppinen
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Abstract

The isostructural double perovskites Ba$_2$CuTeO$_6$ and Ba$_2$CuWO$_6$ are shown by theory and experiment to be frustrated square-lattice antiferromagnets with opposing dominant magnetic interactions. This is driven by differences in orbital hybridisation of Te$^{6+}$ and W$^{6+}$. A spin-liquid-like ground state is predicted for Ba$_2$Cu(Te$_{1-x}$W$_x$)O$_6$ solid solution similar to recent observations in Sr$_2$Cu(Te$_{1-x}$W$_x$)O$_6$.

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O. Mustonen, S. Vasala, H. Mutch, C. I. Thomas, G. B. G. Stenning, E. Baggio-Saitovitch, E. J. Cussen, M. Karppinen. 2018-12-13. Magnetic interactions in the $S = 1/2$ square-lattice antiferromagnets Ba$_2$CuTeO$_6$ and Ba$_2$CuWO$_6$: parent phases of a possible spin liquid. https://doi.org/10.1039/c8cc09479a

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