title: Domain state and exchange coupling in MnPt with Co clusters.
abstract: This Letter reports on the exchange coupling between nanometric Co clusters and disordered MnPt thin films. It is found that, under field-cooling, the MnPt develops a bulk magnetization M_{AF}. The correlation between M_{AF} and the exchange bias H_{b} is studied using a different field-cooling procedure. From this, using a mean-field approach, it is shown that the effective field acting on the interface magnetization responsible for H_{b} is proportional to M_{AF}. This results is strong evidence in favor of the domain state model for exchange bias, in which H_{b} is correlated with the bulk magnetic state of the antiferromagnet, and not only restricted to its interface configuration.
authors.affiliation: CEA Grenoble, DRFMC/SP2M, 17 rue des Martyrs, 38054 Grenoble cedex 9, France. robert.morel@cea.fr
authors.forename: Robert
authors.initials: R
authors.lastname: Morel
authors.forename: Céline
authors.initials: C
authors.lastname: Portemont
authors.forename: Ariel
authors.initials: A
authors.lastname: Brenac
authors.forename: Lucien
authors.initials: L
authors.lastname: Notin