Effect of Oxygen Content on the Superconducting Properties of Nd1+xBa2-xCu3O7-δ (x=0.0, 0.1, 0.2, 0.3, and 0.4)

We investigated the superconducting properties of Nd1+xBa2-xCu3O7-δ with x=0.0, 0.1, 0.2, 0.3, and 0.4 as a function of the oxygen content. The temperature variation of the oxygen content was studied by means of both TG-DTA and an iodometric titration technique. The amount of oxygen absorbed during oxygenation decreases with increasing x. We have also studied the effect of the oxygen content on the superconducting properties for the samples with various x. It was found that the optimum annealing temperature for the highest T c is higher for larger x.