Phaseseparation in overdoped Y1−0.8Ca0−0.2Ba2Cu3O6.96−6.98
نویسنده
چکیده
The dimpling in the CuO2 planes of overdoped Y1−yCayBa2Cu3 O6.96−6.98, (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 by Ca to be trapped at the Ca sites and their nn environment.
منابع مشابه
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