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arXiv · 1303.3398

Investigation of charge states and multiferroicity in Fe-doped h-YMnO3

Sonu Namdeo·A. K. Sinha·M. N. Singh·A. M. Awasthi
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Abstract

Polycrystalline YMn1-xFexO3 (YMFO_x) (0 <= x <= 0.1) compounds have been prepared in single phase and characterized by synchrotron X-ray diffraction, X-ray absorption near edge spectroscopy, magnetization, and dielectric measurements. Iron-substitution in hexagonal YMnO3 causes intra-lattice changes exceeding those of the lattice cell. XANES provide mixed-valence Mn3+/Mn4+ and Fe4+ charge states in these manganites, consistent with the observed decrease of the effective magnetic moment with Fe-doping. Magnetization M(T) evidence antiferromagnetic (AFM) ordering of the specimens with little weak ferromagnetism, and the metrices of exchange interaction suppress with Fe-doping, attributed to the lengthening of the Mn-O planar bond lengths. Dielectric {\epsilon}'(T) results showing highly doping-dependent anomaly at T_N indicate linear magneto-electric coupling.

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Sonu Namdeo, A. K. Sinha, M. N. Singh, A. M. Awasthi. 2013-03-14. Investigation of charge states and multiferroicity in Fe-doped h-YMnO3. https://doi.org/10.1063/1.4794831

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