Domain state model for exchange bias: thickness dependence of diluted antiferromagnetic Co1−yO on exchange bias in Co/CoO

Abstract The thickness dependence of different diluted antiferromagnetic Co 1− y O layers on the exchange bias (EB) in ferro/antiferromagnetic Co/Co 1− y O bilayers is investigated. For undiluted samples the EB decreases above a layer thickness of 5 nm whereas it increases and saturates for AFM layers thicker than 20 nm for diluted samples. These findings support the domain state model for EB.