Field free magnetization switching in perpendicularly magnetized Pt/Co/FeNi/Ta structure by spin orbit torque
Field free magnetization switching in perpendicularly magnetized Pt/Co/FeNi/Ta structure by spin orbit torque
复制标题
垂直磁化 Pt/Co/FeNi/Ta 结构中自旋轨道力矩的无场磁化翻转
DOI：
10.1063/5.0025132
复制
发表时间：
2020-10-05
影响因子：
4
通讯作者：
Xi, Li
中科院分区：
文献类型：
--
作者：
Chang, Meixia;Yun, Jijun;Xi, Li
垂直磁化薄膜中自旋轨道力矩驱动的磁化翻转依赖于额外的面内磁场来打破面内磁对称性，这是自旋轨道力矩驱动自旋电子器件集成化的一个障碍。在这里，我们提出了一个简单的方法来实现无场自旋轨道转矩驱动的磁化翻转利用倾斜的磁各向异性，这是由两个铁磁层的直接耦合在Pt/Co/FeNi/Ta结构。在制备样品时，施加1000 Oe的面内磁场，以确保磁矩从面外方向与该面内场方向偏离一个小角度。我们实验证明了确定性的无场磁化翻转Pt/Co/FeNi/Ta的类场自旋轨道转矩时，电流施加垂直于这个面内场方向。由于引入FeNi层后自旋-轨道矩效率和垂直磁各向异性略有下降，开关性能略有下降，临界开关电流密度和热稳定因子分别达到6.4 × 10（6）A/cm（2）和25。我们的工作为利用自旋轨道力矩实现无场磁化翻转奠定了基础。
Spin orbit torque-driven magnetization switching in perpendicularly magnetized thin film relies on an extra in-plane magnetic field to break the in-plane magnetic symmetry, which is an obstacle for the integration of spin-orbit torque-based spintronic devices. Here, we propose a simple method to realize the field-free spin-orbit torque-driven magnetization switching by exploiting a tilted magnetic anisotropy, which is caused by the direct coupling of two ferromagnetic layers in the Pt/Co/FeNi/Ta structure. When preparing the sample, a 1000Oe in-plane magnetic field was applied to ensure the magnetic moment deviating a small angle from the out-of-plane direction to this in-plane field direction. We experimentally demonstrate the deterministic field-free magnetization switching in Pt/Co/FeNi/Ta by the field-like spin-orbit torques when the electric current is applied perpendicular to this in-plane field direction. The switching performance is slightly degraded with the critical switching current density and thermal stability factor, respectively, reaching 6.4x10(6) A/cm(2) and 25 due to the slightly decreased spin-orbit torque efficiency and perpendicular magnetic anisotropy with introducing the FeNi layers. Our work paves the way for realizing the field-free magnetization switching by spin-orbit torques.