Guo Zongxia, Wang Junlin, Malinowski Gregory, Zhang Boyu, Zhang Wei, Wang Hangtian, Lyu Chen, Peng Yi, Vallobra Pierre, Xu Yong, Xu Yongbing, Jenkins Sarah, Chantrell Roy W, Evans Richard F L, Mangin Stéphane, Zhao Weisheng, Hehn Michel
Fert Beijing Institute, School of Integrated Science and Engineering, Beihang University, Beijing, 100191, China.
Institut Jean Lamour, UMR CNRS, Université de Lorraine, Nancy, 54011, France.
Adv Mater. 2024 May;36(21):e2311643. doi: 10.1002/adma.202311643. Epub 2024 Mar 3.
Ultrafast manipulation of magnetic order has challenged the understanding of the fundamental and dynamic properties of magnetic materials. So far single-shot magnetic switching has been limited to ferrimagnetic alloys, multilayers, and designed ferromagnetic (FM) heterostructures. In FM/antiferromagnetic (AFM) bilayers, exchange bias (H) arises from the interfacial exchange coupling between the two layers and reflects the microscopic orientation of the antiferromagnet. Here the possibility of single-shot switching of the antiferromagnet (change of the sign and amplitude of H) with a single femtosecond laser pulse in IrMn/CoGd bilayers is demonstrated. The manipulation is demonstrated in a wide range of fluences for different layer thicknesses and compositions. Atomistic simulations predict ultrafast switching and recovery of the AFM magnetization on a timescale of 2 ps. The results provide the fastest and the most energy-efficient method to set the exchange bias and pave the way to potential applications for ultrafast spintronic devices.
对磁序的超快操控对理解磁性材料的基本和动态特性提出了挑战。到目前为止，单次磁开关仅限于亚铁磁合金、多层膜以及设计的铁磁（FM）异质结构。在FM/反铁磁（AFM）双层膜中，交换偏置（H）源于两层之间的界面交换耦合，并反映了反铁磁体的微观取向。本文展示了在IrMn/CoGd双层膜中用单个飞秒激光脉冲实现反铁磁体单次开关（H的符号和幅度变化）的可能性。在不同层厚度和成分的广泛能量密度范围内都证明了这种操控。原子模拟预测在2皮秒的时间尺度上AFM磁化强度会有超快开关和恢复。这些结果提供了设置交换偏置的最快且最节能的方法，并为超快自旋电子器件的潜在应用铺平了道路。
