合成反铁磁体(SAF)是一种出色的系统,可通过调整层厚度和材料成分来控制磁耦合。这里,我们控制垂直磁化SAFPt/Co/Ir/CoFeB/MgO多层膜中的层间交换耦合(IEC),通过改变非磁性层Ir厚度和磁性层Co厚度来调节。并且我们研究了自旋轨道转矩(SOT)驱动的SAF磁化切换。在IEC较弱的SAF中,SOT驱动的开关行为类似于单个铁磁体系统,由外部磁场主导。相比之下,在拥有超强IEC的SAF中,饱和磁场大于50kOe,SOT驱动的开关行为由有效磁场决定。有效磁场与外部磁场相关,IEC领域,CoFeB和Co的磁矩,和磁各向异性。这些结果可以促进对垂直SAF的SOT切换的理解,并促进具有低杂散场和较低功率的SAF在自旋电子器件中的应用。
Synthetic antiferromagnet (SAF) is an outstanding system for controlling magnetic coupling via tuning the layer thickness and material composition. Here, we control the interlayer exchange coupling (IEC) in a perpendicularly magnetized SAF Pt/Co/Ir/CoFeB/MgO multilayer, which is tuned by varying the nonmagnetic layer Ir thickness and the magnetic layer Co thickness. And we study the spin-orbit torque (SOT) driven magnetization switching of the SAF. In the SAF with a weak IEC, the SOT-driven switching behavior is similar to that of a single ferromagnet system, which is dominated by the external magnetic field. In contrast, in the SAF with an ultra-strong IEC, the saturation magnetic field is large than 50 kOe, and the SOT-driven switching behavior is decided by the effective magnetic field. The effective field is correlated to the external magnetic field, the IEC field, magnetic moments of CoFeB and Co, and magnetic anisotropy. These results may advance the understanding of SOT switching of perpendicular SAFs and promote the applications of SAFs with low stray fields and lower power in spintronic devices.