Oxygen kinetics and superconductivity in the high-T/sub c/ oxide YBa/sub 2/Cu/sub 3/O/sub x/

Disk-shaped samples of the nominal compositions YBa/sub 2/Cu/sub 3/O/sub 7/, Y/sub 2/BaCuO/sub 5/ and BaCuO/sub 2/ were initially produced through the solid diffusion method. These samples were then cut into several small pieces, which were used for oxygen intercalation and desorption studies for temperatures between 330 degrees C and 700 degrees C. The compound YBa/sub 2/Cu/sub 3/O/sub x/ went through a gradual transformation, going from the pure superconducting orthorhombic phase (x=7.0) to the pure semiconducting tetragonal phase (x=6.3). The compound BaCuO/sub y/ also varied its oxygen content, in the range 2.00>