Nota de FísicaPublicado
$57$ Fe Mössbauer Studies on Semiconducting and Superconducting La-Ba-Cu-O
E. M. B. Saitovitch; R. B. Scorzelli; Izabel de Souza Azevedo; C.A. dos Santos; F.J. Litterst
1989
Dados da publicação
- Autores
- E. M. B. Saitovitch; R. B. Scorzelli; Izabel de Souza Azevedo; C.A. dos Santos; F.J. Litterst
- Tipo
- Nota de Física
- Status
- Publicado
- Data de publicação
- 1989
- Descrição
- La<sub>2–x</sub>Ba<sub>x</sub>CuO<sub>4</sub> samples substituted with <sup>57</sup>Fe (less than 1%) were studied for 0 <math>\le</math> x <math>\le</math> 0.35. Despite the fact that there is only one Cu site which can be occupied by the iron-substituent, the <sup>57</sup>Fe Mössbauer spectra at room temperature show three quadrupole doublets whose intensities were followed in different steps of sample preparation. They are characteristic of Fe<sup>3+</sup>, and their Mössbauer parameters depend on the Ba content. One of the iron species may be due to defects since it disappears by further heat treatment, while the others are present even in the undoped La<sub>2</sub>Cu0<sub>4</sub>. Magnetic ordering has been found at 4.2 K for samples with 0.5% Fe even in the superconducting samples with x = 0.15.
- Ano
- 1989
- Número
- CBPF-NF-056/89
- Vínculo com tese
- Não
- Vínculo com bolsa
- Não