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arXiv · 1909.05002

Natural ferroelectric order near ambient temperature in HoFeO3: A member of RFeO3 orthoferrites

K. Dey·A. Indra·S. Mukherjee·S. Majumdar·J. Strempfer·O. Fabelo·E. Mossou·5 T. Chatterji·S. Giri
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Abstract

Current scenario in multiferroics demands a breakthrough discovery of promising materials after BiFeO3. Recently, the controversial discovery of room temperature ferroelectricity (FE) in SmFeO3 [PRL 107, 117201 (2011); 113, 217203 (2014)] inspires the investigation of HoFeO3. Here, we report a natural ferroelectric order below 210 K (TFE) along c-axis with reasonably large polarization and low-field strong magnetoelectric coupling. Synchrotron and neutron diffraction results confirm that a shift of O atoms along c-axis of polar Pbn21 structure causes FE in HoFeO3. The exchange striction mechanism is suggested to elucidate the ferroelectric order. The results create a renewed attention for searching promising candidates with a natural ferroelectric order and higher TFE in the rest of the RFeO3 series.

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K. Dey, A. Indra, S. Mukherjee, S. Majumdar, J. Strempfer, O. Fabelo, E. Mossou, 5 T. Chatterji, S. Giri. 2019-09-11. Natural ferroelectric order near ambient temperature in HoFeO3: A member of RFeO3 orthoferrites. https://doi.org/10.1103/physrevb.100.214432

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