Zheng Zhenyi, Zhang Zhizhong, Feng Xueqiang, Zhang Kun, Zhang Yue, He Yu, Chen Lei, Lin Kelian, Zhang Youguang, Khalili Amiri Pedram, Zhao Weisheng
Fert Beijing Institute, MIIT Key Laboratory of Spintronics, School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China.
Department of Electrical and Computer Engineering, Northwestern University, Evanston, Illinois 60208, United States.
ACS Nano. 2022 May 24;16(5):8264-8272. doi: 10.1021/acsnano.2c02031. Epub 2022 Apr 21.
Spin-orbit torque (SOT) is widely considered as an effective route to manipulate magnetic order in spintronic devices. The low power consumption and long endurance demands from future computer architectures urgently require a reduction of the critical SOT switching current density, . However, except for searching for a SOT source with a high-spin Hall angle, few efficient mechanisms to reduce have been proposed. In this work, we achieved an anomalous thermal-assisted (TA) reduction in a Pt/Co/Tb heterostructure through engineering a ferrimagnetic Co/Tb interface. This reduction tendency is demonstrated to be strongly dependent on the thickness of Tb, . When reaches an optimal point (3 nm), a 74 K temperature increase will reduce by more than an order of magnitude (17 times). Comparison experiments and theoretical simulations indicate that this anomalous TA reduction behavior goes beyond the conventional SOT framework and originates from the temperature-sensitive ferrimagnetic interface. We further propose a multifunctional logic-in-memory device, where six different Boolean logic gates can be implemented, to demonstrate the application potential and energy efficiency of this TA SOT switching mechanism. Our work provides an effective alternative to reduce in SOT devices and may inspire future spintronic memory, logic, and high-frequency devices.
自旋轨道矩(SOT)被广泛认为是在自旋电子器件中操纵磁序的有效途径。未来计算机架构对低功耗和长耐久性的需求迫切要求降低临界SOT开关电流密度。然而,除了寻找具有高自旋霍尔角的SOT源之外,很少有能有效降低该电流密度的机制被提出。在这项工作中,我们通过设计亚铁磁Co/Tb界面,在Pt/Co/Tb异质结构中实现了反常热辅助(TA)电流密度降低。这种电流密度降低趋势被证明强烈依赖于Tb的厚度。当Tb厚度达到最佳点(3 nm)时,温度升高74 K将使电流密度降低超过一个数量级(17倍)。对比实验和理论模拟表明,这种反常的TA电流密度降低行为超出了传统的SOT框架,源于对温度敏感的亚铁磁界面。我们进一步提出了一种多功能逻辑存储一体器件,其中可以实现六种不同的布尔逻辑门,以展示这种TA SOT开关机制的应用潜力和能量效率。我们的工作为降低SOT器件中的电流密度提供了一种有效的替代方案,并可能启发未来的自旋电子存储器、逻辑器件和高频器件。