Abstract
In order to explore the spin structure in the ferromagnetic/antiferromagnetic exchange-coupled layers, the magnetization process was studied for NiFe/NiO/CoPt trilayers as well as NiFe/NiO bilayers. In bilayers with NiO thicknesses of 5 to 10 nm, the coercivity increases with increasing NiO thickness but no loop shift appears. In NiFe/NiO/CoPt trilayers, the loop shift of the NiFe layer appears even for very thin(<10 nm) NiO layers, and the direction of the shift coincides with that of the magnetization of the hard-magnetic CoPt layer. This suggests that the spin directions in the very thin NiO layer, which are aligned antiferromagnetically, are totally reversed throughout the NiO layer by reversing the magnetization of the CoPt layer.
