Experimental Analysis of YBa2Cu3Ox/Ag Proximity Interfaces

Abstract
We have fabricated SNS (superconductor-normal metal-superconductor) junctions consisting of YBa2Cu3O x (YBCO)/Ag/Nb trilayers in order to probe surface properties of the YBCO films. The trilayers are in situ deposited, and patterned by a photolithographic technique. These junctions exhibit Josephson-like behavior. The contact resistivity and its temperature dependence suggest that the weaklinks are formed inside YBCO and that the junction properties depend on the area of surface non-superconducting phases consisting of the YBCO components.