Magnetic behaviour investigation on symmetric spin valves of Co/Cu/NiFe and NiFe/Cu/Co

In this paper, we have obtained and investigated the magnetic behaviours of the ferromagnetic layer in the symmetric spin valves of Co/Cu/NiFe and NiFe/Cu/Co by measuring with a vibrating sample magnetometer and analysing in terms of the multi-domain Ising models. It has been found that some magnetic layer can have quite different magnetic behaviours in different structures of spin valves, depending on the properties of the under-layer. In our investigation, we have found that the magnetic behaviour of a Co layer depends mainly on the magnetization of the under-layer, whereas this is not the case for the NiFe layer.