Superconducting behaviour of Y0·8Ce0·1Ca0·1Ba2Cu4O8

Abstract The superconducting behaviour of Y0·8Ce0·1Ca0·1Ba2Cu4O8 synthesized under ambient oxygen pressure, is analysed in comparison to that of pure YBa2Cu4O8, Y0·9Ce0·1Ba2Cu4O8 and Y0·9Ca0·1Ba2Cu4O8. It is observed that counter-substitution of Ca at Y sites in Y0·9Ca0·1Ba2Cu4O8 does not restore the value of T c to that of the parent compound YBa2Cu4O8. This supports the conjecture that not all of the Ca2+ ions may be occupying Y sites.

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