Exchange coupling mechanism for magnetization reversal and thermal stability of Co nanoparticles embedded in a CoO matrix
نویسندگان
چکیده
A model providing a semi-quantitative account for the magnetic behavior of Co nanoparticles embedded in a CoO matrix is presented. The results confirm that exchange coupling at the interface between FM and AFM nanostructures, could provide an extra source of magnetic anisotropy, leading to thermal stability of the FM nanoparticles. It is shown that perpendicular coupling between the AFM and FM moments may result in large coercivities. The energy barrier, which works against reversal is due to the AFM susceptibility anisotropy. Experimentally observed exchange-bias is tentatively ascribed to preexisting intrinsic canting of the AFM moments at the interface. © 2010 Elsevier B.V. All rights reserved PACS: 75.50.Tt; 7530.Gw; 75.70.Cn
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