Abstract:
Antiferromagnets are competitive candidates for the next generation of spintronic devices owing to their superiority in small-scale and low-power-consumption devices. The electrical manipulation of the magnetization and exchange bias (EB) driven by spin-orbit torque (SOT) in ferromagnetic (FM)/antiferromagnetic (AFM) systems has become focused in spintronics. Here, the realization of a large perpendicular EB field in Co/IrMn and the effective manipulation of the magnetic moments of the magnetic Co layer and EB field by SOT in Pt/Co/IrMn system is reported. During the SOT-driven switching process, an asymmetrically manipulated state is observed. Current pulses with the same amplitude but opposite directions induce different magnetization states. Magneto-optical Kerr measurements reveal that this is due to the coexistence of stable and metastable antiferromagnetic domains in the AFM. Exploiting the asymmetric properties of these FM/AFM structures, five spin logic gates, namely AND, OR, NOR, NAND, and NOT, are realized in a single cell via SOT. This study provides an insight into the special ability of SOT on AFMs and also paves an avenue to construct the logic-in-memory and neuromorphic computing cells based on the AFM spintronic system.
摘要:
反铁磁体由于其在小规模和低功耗设备中的优势而成为下一代自旋电子器件的竞争性候选者。在铁磁(FM)/反铁磁(AFM)系统中,由自旋轨道转矩(SOT)驱动的磁化和交换偏置(EB)的电操纵已成为自旋电子学的重点。这里,报道了在Co/IrMn中实现大的垂直EB场,以及在Pt/Co/IrMn系统中SOT对磁性Co层和EB场的磁矩的有效操纵。在SOT驱动的开关过程中,观察到非对称操纵状态。具有相同振幅但方向相反的电流脉冲引起不同的磁化状态。磁光克尔测量表明,这是由于AFM中稳定和亚稳态的反铁磁畴共存。利用这些FM/AFM结构的不对称特性,五个自旋逻辑门,即AND,OR,NOR,NAND,而不是,通过SOT在单个单元中实现。这项研究提供了对SOT在AFM上的特殊能力的见解,也为基于AFM自旋电子系统构建内存逻辑和神经形态计算细胞铺平了道路。