| Full text | |
| Author(s): |
Garcia, S.
;
Andrade, S.
;
Jardim, R. F.
;
Fonseca, F. C.
;
Torikachvili, M. S.
;
Lacerda, A. H.
Total Authors: 6
|
| Document type: | Journal article |
| Source: | PHYSICAL REVIEW B; v. 80, n. 13, p. 6-pg., 2009-10-01. |
| Abstract | |
A systematic study of magnetoresistance and dc magnetization was conducted in polycrystalline (Ru1-xIrx)Sr2GdCu2O8 [(Ru,Ir)-1212] compounds, for 0 <= x <= 0.15. We found that a deviation from linearity in the normal-state electrical resistivity (rho) curves for temperatures below the magnetic transition temperature T-M < 130 K can be properly described by a logarithmic term. The prefactor C(x, H) of this anomalous ln T contribution to rho(T) increases linearly with the Ir concentration, and diminishes rapidly with increasing applied magnetic field up to H approximate to 4 T, merging with the C(0,H) curve at higher magnetic fields. Correlation with magnetic susceptibility measurements supports a scenario of local perturbations in the orientation of Ru moments induced in the neighborhood of the Ir ions, therefore acting as scattering centers. The linear dependence of the prefactor C(x,H=0) and the superconducting transition temperature T-SC on x points to a common source for the resistivity anomaly and the reduction in T-SC, suggesting that the CuO2 and RuO2 layers are not decoupled. (AU) | |
| FAPESP's process: | 05/53241-9 - Study of intergranular phenomena in ceramic materials |
| Grantee: | Reginaldo Muccillo |
| Support Opportunities: | Research Projects - Thematic Grants |