Nanostructure of granular Co-Si O2 thin films modified by thermal treatment and its relationship with the giant Hall effect
Abstract
Granular cosputtered Co52(SiO2)48 thin films were thermally treated at different temperatures and their magnetotransport and structural properties were investigated. Hall resistivity increases with annealing temperature (Ta) , up to Ta=250°C , and then decreases to a minimum for Ta=400°C . The structural analysis was based on small-angle x-ray scattering results. A model of a polydisperse system of hard spheres was used to retrieve structural parameters. Results reveal that a volume fraction of Co atoms (approximately 25%) are forming nanospheres. The giant Hall effect depends on a particular combination of nanoparticle diameter, size distribution, and interparticle distance.
- Publication:
-
Physical Review B
- Pub Date:
- November 2005
- DOI:
- 10.1103/PhysRevB.72.184423
- Bibcode:
- 2005PhRvB..72r4423S
- Keywords:
-
- 78.70.Ck;
- 75.50.Tt;
- 73.63.Bd;
- X-ray scattering;
- Fine-particle systems;
- nanocrystalline materials;
- Nanocrystalline materials