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arXiv · 2202.01491

Magnetism of Al$_x$Fe$_{2-x}$GeO$_5$ with Andalusite Structure

K. Kakimoto·S. Takada·H. Ohta·Y. Haraguchi·M. Hagihala·S. Torii·T. Kamiyama·H. Mitamura·M. Tokunaga·A. Hatakeyama·H. Aruga Katori
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Abstract

The magnetism of Al$_x$Fe$_{2-x}$GeO$_5$ from $x$ = 0.09 to $x$ = 0.91 with andalusite structure was examined. The magnetic properties of Al$_x$Fe$_{2-x}$GeO$_5$ at low temperatures were found to be weak ferromagnetic-like state for $x$ $<$ 0.3 and spin-glass state for $x$ $>$ 0.3. The small spontaneous magnetization that appears in the weak ferromagnetic-like phase would be due to the presence of Dzyaloshinsky-Moriya interaction or to the difference in the magnitude of the magnetic moment of Fe$^{3+}$ in the octahedral and trigonal bipyramidal sites. The appearance of the spin-glass phase indicates that the dilution of Fe ions by Al ions in Al$_x$Fe$_{2-x}$GeO$_5$ causes the competition between ferromagnetic and antiferromagnetic interactions. The $x$ dependence of the site occupancy of Fe ions suggests that Fe$_2$GeO$_5$ with andalusite structure cannot be synthesized.

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K. Kakimoto, S. Takada, H. Ohta, Y. Haraguchi, M. Hagihala, S. Torii, T. Kamiyama, H. Mitamura, M. Tokunaga, A. Hatakeyama, H. Aruga Katori. 2022-02-03. Magnetism of Al$_x$Fe$_{2-x}$GeO$_5$ with Andalusite Structure. https://doi.org/10.7566/jpsj.91.054704

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