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

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 Added by Hiroki Wadati
 Publication date 2011
  fields Physics
and research's language is English




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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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