Abstract
The Hall coefficient , the volume fraction showing the Meissner effect, and the superconducting transition temperature have been measured in the high- oxide for a range of oxygen vacancy concentration . We find that , , and are insensitive to over the range . In this range, superconductivity at 55 K is possible (with a carrier density of 1.4× ), even with severe loss of connectivity in the CuO chains. The data are consistent with superconductivity occurring only in the CuO planes. A sharp transition in is also seen when exceeds 0.50.
- Received 29 July 1987
DOI:https://doi.org/10.1103/PhysRevB.36.7222
©1987 American Physical Society