Temperature dependence of the complex magnetic susceptibility for the oxidic Y1-xZrxBa2Cu3O7-delta superconductors

The thermal variation of the complex magnetic susceptibility chi(T) = chi'( T) + i chi"(T) for the oxidic superconducting compounds Y1-xZrxBa2Cu3O7-del ta x = 0.01, 0.05 and 0.10 was investigated. The real part of the complex m agnetic susceptibility chi' (T) below critical temperature T-c(chi) is nega tive and is lost in two stages when the temperature decreases. The inflexio n point on the chi'(T) curve corresponds to the two peaks on the temperatur e dependence of the imaginary part, chi"(T), of the complex magnetic suscep tibility and represents the critical temperatures for the intergranular sup erconductivity T-pi(1) i = 1, 2, 3 and for the intragranular superconductiv ity T-pi(2), i = 1, 2, 3. The concentration dependence of the critical temp eratures is almost linear for the investigated compounds Y1-xZrxBa2Cu3O7-de lta, x = 0.01, 0.05 and 0.10. The presence of the second weak peak or its a bsence on the chi"(T) curves at T-pi(2) < T-c(chi) characterizes an intense intergranular coupling.