Novel High-Tc Superconducting Phase of the Y-Ba-Cu-O Compound

Abstract
A novel high-T c superconducting phase is found in the oxide Y-Ba-Cu-O. A sample with nominal composition Ba0.5Y0.5CuO3-d shows a sharp superconducting transition at 92.6 K with a width as narrow as 0.9 K. The Electron Probe Micro Analyzer (EPMA) data and the X-ray powder diffraction pattern show that the high T c superconducting phase has the tetragonal oxygen-defect perovskite (ODP) structure with composition Y2Ba4Cu6O14+y .