XPS SPECTRA OF Y-Ba-Cu-O AND ITS DOPED SYSTEMS

Abstract

An XPS study was carried out on the samples of pure Y-Ba-Cu-O and its doped systems. The experiment gave several important results about the electronic states of Y-Ba-Cu-O system. First, the presence of Cu 3+ oxidation state has correlation with the oxygen content and the formal valence state of Cu , but has no direct relationship with the magnitude of Tc; second, there is strong correlation among the electronic states of O, Ba and Cu ; third, the subtle difference in the electronic states of the elements may induce local structure change.