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A 4-unit-cell superstructure in optimally doped YBa2Cu3O6.92 superconductor

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 نشر من قبل Zahirul Islam
 تاريخ النشر 2003
  مجال البحث فيزياء
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Using high-energy diffraction we show that a 4-unit-cell superstructure, q0=(1/4,0,0), along the shorter Cu-Cu bonds coexists with superconductivity in optimally doped YBCO. A complex set of anisotropic atomic displacements on neighboring CuO chain planes, BaO planes, and CuO2 planes, respectively, correlated over ~3-6 unit cells gives rise to diffuse superlattice peaks. Our observations are consistent with the presence of Ortho-IV nanodomains containing these displacements.



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