HEAT-TREATMENT INFLUENCE ON THE MAGNETIC AND ELECTRIC PROPERTIES OF HIGH-TcYBa2Cu3O7−δ SUPERCONDUCTOR

Abstract

The changes in the temperature dependences of the magnetic susceptibility and the electrical resistivity of a very-high-T c superconducting YBa 2 Cu 3 O 7−δ sample during the thermal cycling between the liquid-nitrogen temperature and the room temperature are studied. Some singularities corresponding to the superconducting transition, the possible existence of a super-high-temperature superconducting phase and the migration of the oxygen atoms in the Cu-O chains are emphasized on these dependencies.