Magnetic characterization of a thin Co2MnSi/L10–MnGa synthetic antiferromagnetic bilayer prepared by MBE**Project supported by the National Program on Key Basic Research Project, China (Grant No. 2018YFB0407601), the Key Research Project of Frontier Science of the Chinese Academy of Sciences (Grant Nos. QYZDY-SSW-JSC015 and XDPB12), and the National Natural Science Foundation of China (Grant Nos. 11874349 and 11774339).

Abstract

A synthetic antiferromagnet based on a thin antiferromagnetically coupled Co2MnSi/MnGa bilayer with Pt capping is proposed in this work. Square magnetic loops measured by anomalous Hall effect reveal that a well perpendicular magnetic anisotropy is obtained in this structure. A very large coercivity of 83 kOe (1 Oe = 79.5775 A⋅m−1) is observed near the magnetic moment compensation point of 270 K, indicating an antiferromagnetic behavior. Moreover, the anomalous Hall signal does not go to zero even at the magnetic compensation point, for which the difficulty in detecting the conventional antiferromagnets can be overcome. By changing the temperature, the polarity of the spin–orbit torque induced switching is changed around the bilayer compensation point. This kind of thin bilayer has potential applications in spin–orbit-related effects, spintronic devices, and racetrack memories.