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arXiv · 1309.2892

Nonlinear pressure dependence of T_N in almost multiferroic EuTiO_3

Z. Guguchia·K. Caslin·R. Kremer·H. Keller·A. Shengelaya·A. Maisuradze·J. L. Bettis Jr.·J. Kohler·A. Bussmann-Holder·M. -H. Whangbo
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Abstract

The antiferromagnetic (AFM) phase transition temperature T_N of EuTiO_3 has been studied as a function of pressure p. The data reveal a nonlinear dependence of T_N on p with T_N increasing with increasing pressure. The exchange interactions exhibit an analogous dependence on p as T_N (if the absolute value of the nearest neighbor interaction is considered) and there is evidence that the AFM transition is robust with increasing pressure. The corresponding Weiss temperature Θ_W remains anomalous since it always exhibits positive values. The data are analyzed within the Bloch power law model and provide excellent agreement with experiment.

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Z. Guguchia, K. Caslin, R. Kremer, H. Keller, A. Shengelaya, A. Maisuradze, J. L. Bettis Jr., J. Kohler, A. Bussmann-Holder, M. -H. Whangbo. 2013-09-11. Nonlinear pressure dependence of T_N in almost multiferroic EuTiO_3. https://doi.org/10.1088/0953-8984%2F25%2F37%2F376002

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