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arXiv · 1104.4032

Magnetic properties of the ferrimagnetic cobaltite CaBaCo4O7

Zhe Qu·Langsheng Ling·Lei Zhang·Li Pi·Yuheng Zhang
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Abstract

The magnetic properties of the ferrimagnetic cobaltite CaBaCo$_4$O$_7$ are systematically investigated. We find that the susceptibility exhibits a downward deviation below $\sim$ 360 K, suggesting the occurrence of short range magnetic correlations at temperature well above $T_C$. The effective moment is determined to be 4.5 $μ_B$/f.u, which is consistent with that expected for the Co$^{2+}$/Co$^{3+}$ high spin species. Using a criterion given by Banerjee [Phys. Lett. \textbf{12}, 16 (1964)], we demonstrate that the paramagnetic to ferrimagnetic transition in CaBaCo$_4$O$_7$ has a first order character.

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Zhe Qu, Langsheng Ling, Lei Zhang, Li Pi, Yuheng Zhang. 2011-04-20. Magnetic properties of the ferrimagnetic cobaltite CaBaCo4O7. https://doi.org/10.1016/j.ssc.2011.04.013

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