Mössbauer Studies of <math>57Fe</math> Substitution of Cu Ions in Superconducting Oxides

Nota de FísicaPublicado

Mössbauer Studies of $<math>^{57}Fe</math>$ Substitution of Cu Ions in Superconducting Oxides

E. M. B. Saitovitch

1988

Autores: E. M. B. Saitovitch
Tipo: Nota de Física
Status: Publicado
Data de publicação: 1988
Descrição: Since the discovery of high-<math>T_C\,\!</math> superconductivity in <math>YBa_2Cu_30_7\,\!</math> oxides several studies of metal ions substitutions were reported. The observed depression on <math>T_C\,\!</math> without a systematic correlationn with the charge and magnetic moment of Cu substituents claims for more detailed information about its local properties as can be revealed by <math>^{57}Fe\,\!</math> Mossbauer spectroscopy. The results for different iron concentrations combined with the modifications of the superconducting transition are discussed concerning the presence of magnetic moments on the Fe ions and the preferential occupation of Cu(1) sites, recently confirmed by neutron and electron diffraction experiments. The oxygen coordination for the different iron species are proposed on the basis of their dependence on Fe concentration, their behavior at high temperatures as well as the electron diffraction and electron microscopy measurements reported for <math>Fe:YBa_2Cu_30_7\,\!</math> samples.
Ano: 1988
Número: CBPF-NF-080/88
Vínculo com tese: Não
Vínculo com bolsa: Não