Engineered Spin Configuration in Spin Valve With Customized Synthetic Antiferromagnetic Coupling and Perpendicular Magnetic Anisotropy

Manipulation of the spin configuration in multilayer ferromagnetic thin films, especially for ones with synthetic antiferromagnetic (SAF) coupling, is of paramount importance for the construction of various spintronics. Here, perpendicular SAF heterostructures consisting of [Pt/Co]/Ru/[Co/Pt] have been developed. A large saturation field of 0.67 T has been observed, indicating a strong perpendicular antiferromagnetic (AFM) coupling. More importantly, we have fabricated a spin valve giant magnetoresistance (GMR) device based on SAF/Cu/NiFe multilayers. Transformation from in-plane magnetic anisotropy to perpendicular magnetic anisotropy (PMA) has been realized in the top NiFe layer by control of the Cu thickness and thus the interlayer coupling effect. The polarity of the SAF during the magnetization switching process could be customized by the control of the coupling type [ferromagnetic or antiferromagnetic (AFM)] between SAF and top NiFe layer or change of the periodicity of the Co/Pt multilayers. The spin configuration control strategy reported here provides new insights for the design of customized magnetic sensing, recording, and logic devices.