Effects of Oxygen Stoichiometry for Anisotropic Structural Change in Oriented YBa2Cu3Ox

Abstract
The effects of oxygen content on the structural change of highly oriented YBa2Cu3O x have been studied in terms of X-ray diffraction in the temperature range from 77 K to room temperature. It is found that the temperature dependence of the lattice constant c is severely affected by the oxygen content from x=6.83 to 7.00. However, the temperature dependences of the lattice constants a and b are not influenced by the oxygen content in contrast with that of c. Discussions are also given for the anomalous distortion in the Cu-O2 plane through T c in connection with the formation of anisotropic pairing.