| Texto completo | |
| Autor(es): |
Saavedra-Gaona, I. M.
;
Mesquita, F.
;
Cohen, R.
;
Nagamine, L. C. C. M.
;
Parra-Vargas, C. A.
;
Munevar, J.
Número total de Autores: 6
|
| Tipo de documento: | Artigo Científico |
| Fonte: | PHYSICA B-CONDENSED MATTER; v. 695, p. 7-pg., 2024-09-11. |
| Resumo | |
The effect of replacing Y by Gd and Ba by Sr is studied by Fourier Transform Infrared spectroscopy, Fe-57 M & ouml;ssbauer spectroscopy and DC susceptibility measurements. Site disorder is inferred from FTIR and M & ouml;ssbauer spectra using a Maximum-Entropy-Method. A doping dependence of the IR peaks and the hyperfine parameters is explained in terms of bonding energies and electric field gradient variations in the crystal lattice caused by Fe/Cu site disorder. We find an influence of doping on the structural and magnetic properties through a correlation of hyperfine parameters such as the electric quadrupole splitting and the magnetic hyperfine field. We also find that a paramagnetic volume fraction appears for GdBaCuFeO5 that increases upon Sr doping at the Ba site. The different behavior of the susceptibility upon replacing Y by Gd is attributed to the lack of a favorable environment to enable a Gd-Fe or Gd-Cu exchange interaction. (AU) | |
| Processo FAPESP: | 17/20989-8 - EMU concedido no processo 11/19924-2: atualização do PPMS para Evercool-II mais peças, USD 271,932.00 |
| Beneficiário: | Letície Mendonça Ferreira |
| Modalidade de apoio: | Auxílio à Pesquisa - Programa Equipamentos Multiusuários |