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arXiv · 1301.3263

Interplay of 4f-3d Magnetism and Ferroelectricity in DyFeO3

B. Rajeswaran·D. Sanyal·Mahuya Chakrabarti·Y. Sundarayya·A. Sundaresan·C. N. R. Rao
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Abstract

DyFeO3 exhibits a weak ferromagnetism (TNFe ~ 645 K) that disappears below a spin-reorientation (Morin) transition at TSRFe ~ 50 K. It is also known that applied magnetic field induces ferroelectricity at the magnetic ordering temperature of Dy-ions (TNDy ~ 4.5 K). Here, we show that the ferroelectricity exists in the weak ferromagnetic state (TSRFe < T < TN,C) without applying magnetic field, indicating the crucial role of weak ferromagnetism in inducing ferroelectricity. 57Fe Mössbauer studies show that hyperfine field (Bhf) deviates from mean field-like behaviour that is observed in the weak ferromagnetic state and decreases below the onset of spin-reorientation transition (80 K), implying that the Bhf above TSR had additional contribution from Dy-ions due to induced magnetization by the weak ferromagnetic moment of Fe-sublattice and below TSR, this contribution decreases due to collinear ordering of Fe-sublattice. These results clearly demonstrate the presence of magnetic interactions between Dy(4f) and Fe(3d) and their correlation with ferroelectricity in the weak ferromagnetic state of DyFeO3.

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B. Rajeswaran, D. Sanyal, Mahuya Chakrabarti, Y. Sundarayya, A. Sundaresan, C. N. R. Rao. 2013-01-15. Interplay of 4f-3d Magnetism and Ferroelectricity in DyFeO3. https://doi.org/10.1209/0295-5075%2F101%2F17001

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