CHARACTERISTICS OF THE LOW-TEMPERATURE RESISTIVITY OF GRANULAR SUPERCONDUCTOR Ba 2 YCu 3 O 7-δ

We have studied the relation between the low-temperature resistance of single phase Ba 2 YCu 3 O 7-δ and magnetic field, temperature and measuring current. The results show that the resistance behavior varies obviously with the strength and direction of the field as well as the measuring current. We suggest that all the results are associated with the granular structure of the sample.