Abstract
We observed that the superconducting critical temperature Tc(x) of the oxides (R1−xPrx)Ba2Cu3O7−y (R=Er, Y, Dy, Gd, Eu) decreases monotonically with increasing Pr concentration x. Using the reduced parameters Tc/Tc(0) and x/xcr all the experimental data for five studied systems fall onto the theoretical universal curve of Abrikosov and Gor’kov over the reduced Pr concentration regime, x/xcrxcr is the critical concentration of Pr for the complete suppression of superconductivity and Tc(0) is the Tc for undoped material. The consistency of these results suggests a pair‐breaking mechanism which plays a role in depressing superconductivity in these high Tc oxides.