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

Zahirul Islam·X. Liu·S. K. Sinha·J. C. Lang·S. C. Moss·D. Haskel·G. Srajer·P. Wochner·D. R. Lee·D. R. Haeffner·U. Welp
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Abstract

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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Zahirul Islam, X. Liu, S. K. Sinha, J. C. Lang, S. C. Moss, D. Haskel, G. Srajer, P. Wochner, D. R. Lee, D. R. Haeffner, U. Welp. 2003-12-24. A 4-unit-cell superstructure in optimally doped YBa2Cu3O6.92 superconductor. https://doi.org/10.1103/physrevlett.93.157008

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