Magnetic Properties of Composite Anisotropy CoNbZr/Ceramics Multi-Layers

The authors investigated CoNbZr/ceramic multilayer films, in which the anisotropy direction of the CoNbZr layers, separated by only thin ceramic layers, was changed sequentially (hereafter "composite anisotropy multilayer films"). The effect of this new lamination method on the B-H hysteresis loop and magnetic permeability was studied. When there are twelve CoNbZr layers and the angle between the easy-axis direction of successive CoNbZr layers is 45°, a smooth hysteresis loop with low coercivity was obtained. This same film also had a large permeability (μ') and an excellent frequency response. In addition, the μ' values remained unchanged when bias fields of 2 to 3 Oe were applied. This result is significant for applications to magnetic devices, as it contrasts with conventional uniaxial magnetic multilayer films the permeability of which is changed by an applied bias field.