Magnetostatic coupling in multilayer magnetic structure

Many memory designs reduce the influence of de-metizagning fields by semiclosing the flux path by means of a multilayer structure. Some quantitative results concerning the regions of magnetization curling that occur in these structures are presented here. It is shown, for the case of two identical coupled layers, that the width of the curling region is proportional to the square root of the dimensionless quantity , where is the magnetication and the anisotropy constant, and to the geometric mean of the layer thickness and the interlayer separation. The case of a uniaxial layer coupled to an isotropic flux keeper is also examined. The results are compared to those found previously for single-layer films.