Preparation of sandwiched junctions made of different superconductors, Bi{sub}2Sr{sub}2CaCu{sub}2O{sub}(8+y) and YBa{sub}2Cu{sub}3O{sub}(7-x)

摘要

We have fabricated bilayer films using different superconductors, Bi{sub}2Sr{sub}2CaCu{sub}2O{sub}(8+y) (Bi-2212) and YBa{sub}2Cu{sub}3O{sub}(7-x) (YBCO). Transport properties of the bilayer have been investigated using 25μm ×25μm and 50μm×50μm mesa structures. The current versus voltage characteristics showed a flux-flow like behavior at 4.2 K, while the Shapiro steps were observable when a microwave was irradiated to the mesa junction. The results on Shapiro steps were attributed to a Josephson junction formed at the interface between Bi-2212 layer and YBCO layer in the mesa structure.