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Low Symmetry Phase in (001) BiFeO$_3$ Epitaxial Constrained Thin Films

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 نشر من قبل Guangyong Xu
 تاريخ النشر 2005
  مجال البحث فيزياء
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The lattice of (001)-oriented BiFeO$_3$ epitaxial thin film has been identified by synchrotron x-ray diffraction. By choosing proper scattering zones containing the fixed (001) reflection, we have shown that low-symmetry phases similar to a $M_A$ phase exist in the thin film at room temperature. These results demonstrate a change in phase stability from rhombohedral in bulk single crystals, to a modified monoclinic structure in epitaxial thin films.

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