Evidence for pairhyphen;breaking in (R1minus;xPrx)Ba2Cu3O7minus;y(R=Er, Y, Dy, Gd, Eu) systems

摘要

We observed that the superconducting critical temperatureTc(x) of the oxides (R1minus;xPrx)Ba2Cu3O7minus;y(R=Er, Y, Dy, Gd, Eu) decreases monotonically with increasing Pr concentrationx. Using the reduced parametersTc/Tc(0) andx/xcrall the experimental data for five studied systems fall onto the theoretical universal curve of Abrikosov and Gorrsquo;kov over the reduced Pr concentration regime,x/xcr0.6, wherexcris the critical concentration of Pr for the complete suppression of superconductivity andTc(0) is theTcfor undoped material. The consistency of these results suggests a pairhyphen;breaking mechanism which plays a role in depressing superconductivity in these highTcoxides.