Fan Tuo, Khang Nguyen Huynh Duy, Nakano Soichiro, Hai Pham Nam
Department of Electrical and Electronic Engineering, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Tokyo, 152-8550, Japan.
Department of Physics, Ho Chi Minh City University of Education, 280 An Duong Vuong Street, District 5, Ho Chi Minh City, 738242, Vietnam.
Sci Rep. 2022 Feb 22;12(1):2998. doi: 10.1038/s41598-022-06779-3.
Spin orbit torque (SOT) magnetization switching of ferromagnets with large perpendicular magnetic anisotropy has a great potential for the next generation non-volatile magnetoresistive random-access memory (MRAM). It requires a high performance pure spin current source with a large spin Hall angle and high electrical conductivity, which can be fabricated by a mass production technique. In this work, we demonstrate ultrahigh efficient and robust SOT magnetization switching in fully sputtered BiSb topological insulator and perpendicularly magnetized Co/Pt multilayers. Despite fabricated by the magnetron sputtering instead of the laboratory molecular beam epitaxy, the topological insulator layer, BiSb, shows a large spin Hall angle of θ = 10.7 and high electrical conductivity of σ = 1.5 × 10 Ω m. Our results demonstrate the feasibility of BiSb topological insulator for implementation of ultralow power SOT-MRAM and other SOT-based spintronic devices.
具有大垂直磁各向异性的铁磁体的自旋轨道矩（SOT）磁化翻转在下一代非易失性磁阻随机存取存储器（MRAM）中具有巨大潜力。它需要一个具有大自旋霍尔角和高电导率的高性能纯自旋电流源，该电流源可通过大规模生产技术制造。在这项工作中，我们展示了在完全溅射的BiSb拓扑绝缘体和垂直磁化的Co/Pt多层膜中实现的超高效率和稳健的SOT磁化翻转。尽管是通过磁控溅射而非实验室分子束外延制造的，但拓扑绝缘体层BiSb仍表现出大的自旋霍尔角θ = 10.7以及高电导率σ = 1.5×10Ω·m。我们的结果证明了BiSb拓扑绝缘体用于实现超低功耗SOT-MRAM和其他基于SOT的自旋电子器件的可行性。
