Ohshima Ryo, Kohsaka Yuto, Ando Yuichiro, Shinjo Teruya, Shiraishi Masashi
Department of Electronic Science and Engineering, Kyoto University, Nishikyo-ku, Kyoto, 615-8510, Japan.
Sci Rep. 2021 Nov 5;11(1):21779. doi: 10.1038/s41598-021-01310-6.
The spin Hall effect (SHE) and inverse spin Hall effect (ISHE) have played central roles in modern condensed matter physics especially in spintronics and spin-orbitronics, and much effort has been paid to fundamental and application-oriented research towards the discovery of novel spin-orbit physics and the creation of novel spintronic devices. However, studies on gate-tunability of such spintronics devices have been limited, because most of them are made of metallic materials, where the high bulk carrier densities hinder the tuning of physical properties by gating. Here, we show an experimental demonstration of the gate-tunable spin-orbit torque in Pt/NiFe (Py) devices by controlling the SHE using nanometer-thick Pt with low carrier densities and ionic gating. The Gilbert damping parameter of Py and the spin-memory loss at the Pt/Py interface were modulated by ionic gating to Pt, which are compelling results for the successful tuning of spin-orbit interaction in Pt.
自旋霍尔效应（SHE）和逆自旋霍尔效应（ISHE）在现代凝聚态物理中，尤其是在自旋电子学和自旋轨道电子学领域发挥了核心作用，并且人们为发现新型自旋轨道物理以及创制新型自旋电子器件，在基础研究和面向应用的研究方面付出了诸多努力。然而，此类自旋电子器件的栅极可调性研究一直有限，因为它们大多由金属材料制成，其中高的体载流子密度阻碍了通过栅极调控物理性质。在此，我们展示了通过使用具有低载流子密度的纳米厚铂并结合离子栅控来控制自旋霍尔效应，从而在Pt/NiFe（Py）器件中实现栅极可调自旋轨道转矩的实验演示。通过对铂进行离子栅控，调制了Py的吉尔伯特阻尼参数以及Pt/Py界面处的自旋记忆损耗，这是成功调控铂中自旋轨道相互作用的令人信服的结果。
