Magnetic properties of FeCoV film sandwiched by thin soft-magnetic films

Soft magnetization of FeCoV thin films has been examined experimentally. The coercive force of FeCoV films decreases by more than 90% with little reduction in saturation magnetization or changes in magnetization behavior when films are sandwiched between two thin FeNiMo soft-magnetic layers making up about 2% of the total volume. It can be assumed that a magnetic wall, parallel to the film surface and formed at the interface between the soft-magnetic layer and the FeCoV layer, will readily propagate into the FeCoV layer. The thickness of the soft-magnetic layer necessary for the magnetic wall formation is thought to be about 50~100 Å. The reduction in coercive force seems to be related to the anisotropy of the magnetic properties of the thin soft-magnetic layer. In the case of Fe films, however, a reduction in coercive force due to the thin soft-magnetic layer never occurs. Whether the thin soft-magnetic layer has effects on the crystal structure of FeCoV or Fe layers, will be examined experimentally in the future