Electron tunneling in the high-Tcsuperconductor Y-Ba-Cu-O

Abstract
Electron-tunneling measurements were performed in granular and homogeneous samples of Y-Ba-Cu-O, taking advantage of the presence of natural insulating barriers between grains. The results show supercurrents, the superconducting gap, and sharp peaks that can be related to a new mechanism for superconductivity. A phenomenological interpretation of these results is also outlined.