Anomalous doping dependence of the fluctuation-induced diamagnetism in superconductors of YBCO family

A. Lascialfari, A. Rigamonti, L. Romano' +3

SQUID magnetization measurements in oriented powders of Y${}_{1-x}$Ca${}_x$BaCu${}_3$O${}_y$, with $x$ ranging from 0 to 0.2, for $y\approx 6.1$ and $y\approx 6.97$, have bee…