Phaseseparation in overdoped Y_{1-0.8}Ca_{0-0.2}Ba_2Cu_3O_{6.96-6.98}

J. Röhler; C. Friedrich; T. Granzow; E. Kaldis; G. Böttger

doi:10.1063/1.59633

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Phaseseparation in overdoped Y_{1-0.8}Ca_{0-0.2}Ba_2Cu_3O_{6.96-6.98}

J. Röhler·C. Friedrich·T. Granzow·E. Kaldis·G. Böttger

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Abstract

The dimpling in the CuO_2 planes of overdoped Y_{1-y}Ca_yBa_2Cu_3 O_{6.96-6.98} (y=0.02-0.2) has been measured by x-ray absorption-fine- structure spectroscopy (Y-K EXAFS). A step-like decrease around 12% Ca indicates a percolation threshold for distorted sites of 5 cells, and thus phase segregation. We conclude the charge carriers added by substitution of Y{3+} by Ca{2+} to be trapped at the Ca sites and their nn environment.

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J. Röhler, C. Friedrich, T. Granzow, E. Kaldis, G. Böttger. 1999-02-02. Phaseseparation in overdoped Y_{1-0.8}Ca_{0-0.2}Ba_2Cu_3O_{6.96-6.98}. https://doi.org/10.1063/1.59633

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