Oxidation state and site selection of gold in (YBa2Cu3O7 −δ)(1 − x)Au x

  • G. Ganakas
  • M. J. Morgan
  • G. Jakovidis
Papers
Accepted:

Abstract

Recent experiments on the effect of Au substitution on the superconductivity of YBa2Cu3O7 −δ (YBCO) have revealed that Au, unlike most other dopants, enhances the superconducting transition temperature, Tc, by ∼ 2 K at 10 mole % Au. In the present study. X-ray photoelectron spectra, nominally of 4, 6, 8 and 10 mole % Au-doped YBCO, have been obtained. The Au spectra display a relatively intense peak which is the oxidized component associated with the Au 4f7/2 core level, and an additional component that is most probably due to unreacted gold. The binding energy of the oxidized component is consistent with Au+. This observation, together with previous studies, leads us to postulate a structural model in which Au+ substitutes into a two-ligand c-axis co-ordinated Cu(1) site at a Ba-O (4) surface layer.

Keywords

Oxidation Gold Surface Layer Transition Temperature Binding Energy 
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Copyright information

© Chapman & Hall 1995

Authors and Affiliations

  • G. Ganakas
    • 1
  • M. J. Morgan
    • 1
  • G. Jakovidis
    • 1
  1. 1.Department of PhysicsMonash UniversityClaytonAustralia

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