Suppression of superconductivity and normal state electrical transport in Y 1− x Pr x BaSrCu 3 O 7− δ and Y 1− x Pr x Ba 2 Cu 3 O 7− δ systems

The structure, normal state electrical transport and superconducting critical temperatures ( T c ) of Y 1− x Pr x BaSrCu 3 O 7− δ (i.e., Y(Pr)‐1113) and Y 1− x Pr x Ba 2 Cu 3 O 7− δ (i.e., Y(Pr)‐123) systems, with 0.00 ≤ x ≤ 1.00 and 6.93 ≤ 7 − δ ≤ 6.95, have been investigated. Residual resistivity ( ρ 0 ) and resistivity slope ((d ρ /d T ) cc ) corresponding to the linear ρ ‐ T region are determined from the normal state resistivity measurements. It is found that an increase in ρ 0 and (d ρ /d T ) cc correlates with a decrease and enhancement of T c ( x ), respectively. Interestingly, in both the systems, the destruction of superconductivity seems to occur at the same value of x where (d ρ /d T ) cc tends to zero. The observed correlations suggest a possible mechanism of superconductivity in these systems, which is discussed. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)