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arXiv · 1107.2467

Magnetically-Driven Ferroelectric Atomic Displacements in perovskite like YMnO3

D. Okuyama·S. Ishiwata·Y. Takahashi·K. Yamauchi·S. Picozzi·K. Sugimoto·H. Sakai·M. Takata·R. Shimano·Y. Taguchi·T. Arima·Y. Tokura
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Abstract

Magnetically-driven ferroelectric atomic displacements of the order of 10$^{-3} Angstrom have been observed in orthorhombic (perovskite like) YMnO$_3$ by a single-crystal synchrotron x-ray diffraction. The refined polar structure shows the characteristic bond alternation driven by the exchange striction in staggered Mn-O-Mn arrays with $\uparrow\uparrow\downarrow\downarrow$ type ordering, giving rise to a spontaneous polarization along a-axis. First-principles calculations based on the Berry phase method as well as on the experimentally refined crystal structure can reproduce the observed polarization value.

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D. Okuyama, S. Ishiwata, Y. Takahashi, K. Yamauchi, S. Picozzi, K. Sugimoto, H. Sakai, M. Takata, R. Shimano, Y. Taguchi, T. Arima, Y. Tokura. 2011-07-13. Magnetically-Driven Ferroelectric Atomic Displacements in perovskite like YMnO3. https://doi.org/10.1103/physrevb.84.054440

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