材料期刊网

The positron lifetime as a function of the Cd content x was measured for the as-prepared samples of (Pb1-xCdx)Sr-2(Y0.5Ca0.5)Cu2Oy. A constant long-lived Lifetime was observed for all samples. The intensity of the long-lived lifetimes has an obvious decrease starting at x = 0.3 and indicated the existence of an impurity phase in the sample with x = 0.3. The monotonous decrease of the bulk lifetime for the single-phase samples implies that Cd mainly substitutes for Pb. The changes of the microstructure with Cd content were discussed.