Identification of a single-phase Y-Ba-Cu-O system superconducting at 91 K

Abstract

The authors have studied a series of compounds of the type Y_1−xBa_xCuO_y (y undetermined) with the aim of identifying the superconducting phase in the multiphase system Y_1.2Ba_0.8CuO₄ reported recently. The compounds with x=0.65 and 0.7 exhibit zero electrical resistance at 91 K and the onset of diamagnetic susceptibility at 92 K. These compounds are identified to crystallise in the La₃Ba₃Cu₆O₁₄ type tetragonal (or distorted form) structure.