Direct Observation of Oxygen Atoms in a Tetragonal YBa2Cu3O7.7 High-Tc Superconductor by Means of Ultra-High-Resolution High Voltage Electron Microscopy
- 1 January 1992
- journal article
- Published by IOP Publishing in Japanese Journal of Applied Physics
- Vol. 31 (1A) , L59
- https://doi.org/10.1143/jjap.31.l59
Abstract
Using an ultra-high-resolution high-voltage electron microscope (UHR-HVEM) recently installed at National Institute for Research in Inorganic Materials, a tetragonal YBa2Cu3O7.7 crystal was observed for the [001] as well as [100] orientations with the accelerating voltage of 800 kV, where the damage due to electron irradiation is rather suppressed. Dark spots from oxygens were directly detected in addition to those of Y, Ba and Cu atoms. As a result, the crystal structure was confirmed to be similar to that of the tetragonal YBa2Cu3O7-x (x>0.5) crystal so far known. Excess oxygens are considered to be accommodated in the otherwise vacant oxygen sites.Keywords
This publication has 1 reference indexed in Scilit:
- High-Oxygen-Pressure Synthesis of Superconducting Tetragonal YBa2Cu3O7.7Japanese Journal of Applied Physics, 1990