The electrical manipulation of magnetization and exchange bias in antiferromagnet/ferromagnet thin films could be of use in the development of the next generation of spintronic devices. Current-controlled magnetization switching can be driven by spin–orbit torques generated in an adjacent heavy-metal layer, but these structures are difficult to integrate with exchange bias switching and tunnelling magnetoresistance measurements. Here, we report the current-induced switching of the exchange bias field in a perpendicularly magnetized IrMn/CoFeB bilayer structure using a spin–orbit torque generated in the antiferromagnetic IrMn layer. By manipulating the current direction and amplitude, independent and repeatable switching of the magnetization and exchange bias field below the blocking temperature can be achieved. The critical current density for the exchange bias switching is found to be larger than that for CoFeB magnetization reversal. X-ray magnetic circular dichroism, polarized neutron reflectometry measurements and micromagnetic simulations show that a small net magnetization within the IrMn interface plays a crucial role in these phenomena.

反铁磁体/铁磁体薄膜中的磁化和交换偏置的电操纵可用于下一代自旋电子器件的开发。电流控制的磁化开关可由相邻重金属层中产生的自旋轨道转矩驱动，但这些结构难以与交换偏置开关和隧穿磁阻测量集成。在这里，我们报告了使用反铁磁IrMn层中产生的自旋轨道扭矩，在垂直磁化的IrMn / CoFeB双层结构中，电流诱导的交换偏置场的切换。通过操纵电流的方向和幅度，可以实现低于阻塞温度的磁化和交换偏置场的独立且可重复的切换。发现用于交换偏置切换的临界电流密度大于用于CoFeB磁化反转的临界电流密度。X射线磁性圆二色性，极化中子反射法测量和微磁模拟表明，IrMn界面内的小净磁化强度在这些现象中起关键作用。