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arXiv · 1109.2366

Origin of the large polarization in multiferroic YMnO$_3$ thin films revealed by soft and hard x-ray diffraction

H. Wadati·J. Okamoto·M. Garganourakis·V. Scagnoli·U. Staub·Y. Yamasaki·H. Nakao·Y. Murakami·M. Mochizuki·M. Nakamura·M. Kawasaki·Y. Tokura
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Abstract

We investigated the magnetic structure of an orthorhombic YMnO3 thin film by resonant soft x-ray and hard x-ray diffraction. We observed a temperature-dependent incommensurate magnetic reflection below 45 K and a commensurate lattice-distortion reflection below 35 K. These results demonstrate that the ground state is composed of coexisting E-type and cycloidal states. Their different ordering temperatures clarify the origin of the large polarization to be caused by the E-type antiferromagnetic states in the orthorhombic YMnO3 thin film.

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H. Wadati, J. Okamoto, M. Garganourakis, V. Scagnoli, U. Staub, Y. Yamasaki, H. Nakao, Y. Murakami, M. Mochizuki, M. Nakamura, M. Kawasaki, Y. Tokura. 2011-09-12. Origin of the large polarization in multiferroic YMnO$_3$ thin films revealed by soft and hard x-ray diffraction. https://doi.org/10.1103/physrevlett.108.047203

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