Exchange bias effects are investigated in antiferromagnetic- (AF1-) ferromagnetic- (F-) antiferromagnetic (AF2) structures, where the F consists of a [PtCo] multilayer with perpendicular anisotropy and the two AF layers are composed of IrMn. The AF1 and AF2 thicknesses are varied so that the two IrMn layers exhibit different blocking temperatures. After field cooling, enhancements of the coercivity HC and exchange bias field HE are observed in the AF1-F-AF2 structures with respect to the two subsystems with a single AF layer (i.e., AF1-F and F-AF2). For all systems, the magnitude and sign of HE can be subsequently tailored by field cooling processes under fields of different sign while HC remains constant. The net effect of having two AF-F interfaces is roughly the sum of each individual interface contribution. © 2005 The American Physical Society.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 1 Sep 2005|