Magnetic properties of permalloy multilayers with alternating perpendicular anisotropies

This work reports the magnetic properties of sputtered permalloy (Ni₈₀Fe₂₀) multilayers grown changing the anisotropy direction 90° in successive layers. Magnetic measurements show how the saturating field can be controlled by the thickness ratio between different anisotropy layers and how the coercive field is reduced increasing the number of layers. The linearity of the hysteresis loop is also improved when increasing the number of layers. Magnetic measurements are compared to simulations based on a Stoner-Wolfarth magnetization rotation mechanism.