Orthogonal shape/intrinsic anisotropy toggle-mode magnetoresistance random access memory

Magnetization response to in-plane applied fields has been studied, using Stoner-Wohlfarth model, on the bilayer systems of synthetic antiferromagnet having an anisotropy configuration in which the induced intrinsic uniaxial anisotropy is set either parallel or orthogonal to the shape anisotropy. It has been found that the toggle-mode magnetoresistance random access memory operation is possible even when the shape anisotropy exceeds the intrinsic anisotropy to some extent due to the anisotropic effect of the magnetostatic coupling and that the minimum operating field and maximum relative operating field margin are attained when the two anisotropy compensate each other. The optimal operating fields increase with the increase of the absolute value of the total anisotropy constant. However, the tolerance of total anisotropy constant in the positive direction is greater than in the negative direction if zero total anisotropy is chosen to be optimal.