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arXiv · 1012.4564

Influence of the $A$ cation on the low-temperature antiferromagnetism of ordered antiferroelectric $A_2$CoTeO$_6$ perovskites

R. Mathieu·S. A. Ivanov·R. Tellgren·P. Nordblad
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Abstract

We have investigated the structural and magnetic properties of antiferroelectric $A_2$CoTeO$_6$ perovskites with $A$ = Cd, Ca, Sr, Pb, and Ba. All compounds are antiferromagnetic at low temperatures, with the antiferromagnetic transition temperature slightly decreasing with decreasing ionic size of the $A$ cation. Such a decrease in antiferromagnetic interaction is not observed in $A^{2+}_2$Co$M^{6+}$O$_6$ materials with other $M^{6+}$ cations of similar ionic sizes, suggesting that Te$^{6+}$ cations affect the electronic and in turn the magnetic structure of the system.

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R. Mathieu, S. A. Ivanov, R. Tellgren, P. Nordblad. 2010-12-21. Influence of the $A$ cation on the low-temperature antiferromagnetism of ordered antiferroelectric $A_2$CoTeO$_6$ perovskites. https://doi.org/10.1103/physrevb.83.174420

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