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Direct Correlation between Tc and CuO2 Bilayer Spacing in YBa2Cu3O7-x

M. Varela·D Arias·Z. Sefrioui·C. Leon·C. Ballesteros·S. J. Pennycook·J. Santamaria
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Abstract

We report the effects of epitaxial strain and deoxygenation on high quality [YBa2Cu3O7-x (YBCO)_N / PrBa2Cu3O7 (PBCO)_5] (1000 A thick) superlattices, with 1 <= N <= 12 unit cells. High spatial resolution electron energy loss spectroscopy (EELS) shows that strained, fully oxygenated YBCO layers are underdoped. Irrespective of whether underdoping is induced by strain or deoxygenation, X-ray diffraction analysis shows that Tc correlates directly with the separation of the CuO2 bilayers.

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M. Varela, D Arias, Z. Sefrioui, C. Leon, C. Ballesteros, S. J. Pennycook, J. Santamaria. 2002-08-29. Direct Correlation between Tc and CuO2 Bilayer Spacing in YBa2Cu3O7-x. https://doi.org/10.1103/physrevb.66.134517

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