Analysis of exchange bias effect of NiO+NiFe 2O 4 composites
Abstract
Exchange bias (EB) and magnetic properties of ferrimagnetic (FI) NiFe 2O 4 and antiferromagnetic (AFM) NiO bulk composites, prepared by a chemical co-precipitation and post-thermal decomposition method from Fe-doped NiO matrix, have been investigated. Enhanced coercivities and shifted hysteresis loops are still observed for these samples after field cooling. But the vertical magnetization shifts are not observed. In comparison with the bulk samples, a NiO/10% NiFe 2O 4 nanocomposite was also prepared via direct mixture, in which both the horizontal and vertical shift in the hysteresis loops are observed at 10 K. The observed phenomena are explained in terms of interfacial exchange interaction between the two phases and the finite-size effect, respectively.
- Publication:
-
Journal of Magnetism and Magnetic Materials
- Pub Date:
- January 2010
- DOI:
- 10.1016/j.jmmm.2009.08.032
- Bibcode:
- 2010JMMM..322...79H
- Keywords:
-
- 72.80.Tm;
- 75.70.Cn;
- 75.30.Et;
- 75.60.Ej;
- Composite materials;
- Magnetic properties of interfaces;
- Exchange and superexchange interactions;
- Magnetization curves hysteresis Barkhausen and related effects