title: Bulk and interfacial effects in Co-Cr2O3 nanocomposites.
abstract: The exchange bias field has been measured in a set of Co-Cr2O3 nanocomposites in order to distinguish between the bulk and interfacial contributions to H(ex). The studies were carried out on a set of samples prepared by the sol gel technique in which the Co concentration was varied between 30 and 80 wt%. The particle sizes in all samples were carefully controlled so as to enable a comparison of their magnetic properties. Using thermal activation measurements we are able to distinguish between contributions to H(ex) arising from the thermal stability of the antiferromagnetic particles (bulk behaviour) and that due to changing interface density with increasing Co concentration. We have interpreted our results in terms of the independent particle volume model.
authors: Department of Physics, COMSATS Institute of Information Technology, Park Road, Islamabad 44000, Pakistan.
authors: M Farooq
authors: MF
authors: Nasir
authors: Huey Hoon
authors: HH
authors: Hng
authors: K
authors: K
authors: O'grady
authors: Sadia
authors: S
authors: Manzoor
mesh_terms: D002858:Chromium Alloys / Q000737:chemistry*; D003460:Crystallization / Q000379:methods*; D046911:Macromolecular Substances / Q000737:chemistry; D008280:Magnetics; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D013499:Surface Properties
chemical_list: D002858:Chromium Alloys; D046911:Macromolecular Substances