Abstract
Interband and core-level transitions and plasmon resonance in the high-temperature oxide superconductor YBa2Cu3O7-x were studied by transmission electron-energy-loss spectroscopy using an electron microprobe 1/45-10 in size. Both single-crystal and polycrystalline ceramic samples have been examined. No significant change in electronic structure was observed at the grain boundaries. A 13.5-eV interband-transition peak was found to be sensitive to damages created by ion-beam bombardment. © 1988 The American Physical Society.