ISSN:
1434-6036
Keywords:
PACS. 75.30.Vn Colossal magnetoresistance – 61.72.-y Defects and impurities in crystals; microstructure – 72.15.Gd Galvanomagnetic and other magnetotransport effects
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract: A structural study has been performed on the La0.8Sr0.2FexCo1-xO3 (x = 0.025 to 0.3) system displaying large magnetoresistance (MR) at room temperature. A detailed analysis of the crystal structure and microstructure was done by X-ray diffraction (XRD), transmission and scanning electron microscopy (TEM and SEM). The atomic resolution TEM images and the appearing superreflections in the corresponding SAED patterns revealed that a superstructure is formed due to the presence of iron. The correlation between the ordered microstructure and the observed large MR ratio is discussed. 57Fe Mössbauer spectroscopy was utilized to gain information on the valence state of iron in the sample with x = 0.3. The lattice parameters of Fe- doped La0.8Sr0.2FexCo1-xO3 compounds were found to increase monotonously with increasing Fe content. The valence state of iron was found to be Fe3+.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/PL00011125
