Analysis of theNi81Fe19/Fe50Mn50 exchange bias system with a varying Cu spacer thickness and position for partial decoupling

In order to study the role of the exchange interaction at and near the interface, Ni81Fe19/Fe50Mn50 bilayers have been studied, which have an intervening layer of varying thickness and position in the antiferromagnetic Fe50Mn50 layer. The role of the intervening layer is to generate partial exchange decoupling. As a result, samples were obtained, where in one in-plane direction the position of the intervening layer varies from the interface to the top surface of the Fe50Mn50 layer at a constant intervening layer thickness, and in the other in-plane direction the intervening layer thickness varies. Two-dimensional maps of the resulting exchange bias field and the coercive field were obtained from magneto-optic Kerr effect magnetometry measurements. The role of the position and strength of the partial decoupling within the antiferromagnetic layer on the exchange bias effect and the coercive field is discussed.