Shcherbakov Dmitry, Stepanov Petr, Memaran Shahriar, Wang Yaxian, Xin Yan, Yang Jiawei, Wei Kaya, Baumbach Ryan, Zheng Wenkai, Watanabe Kenji, Taniguchi Takashi, Bockrath Marc, Smirnov Dmitry, Siegrist Theo, Windl Wolfgang, Balicas Luis, Lau Chun Ning
Department of Physics, The Ohio State University, Columbus, OH 43210, USA.
National High Magnetic Field Laboratory, Tallahassee, FL 32310, USA.
Sci Adv. 2021 Jan 29;7(5). doi: 10.1126/sciadv.abe2892. Print 2021 Jan.
Spin-orbit coupling (SOC) is a relativistic effect, where an electron moving in an electric field experiences an effective magnetic field in its rest frame. In crystals without inversion symmetry, it lifts the spin degeneracy and leads to many magnetic, spintronic, and topological phenomena and applications. In bulk materials, SOC strength is a constant. Here, we demonstrate SOC and intrinsic spin splitting in atomically thin InSe, which can be modified over a broad range. From quantum oscillations, we establish that the SOC parameter α is thickness dependent; it can be continuously modulated by an out-of-plane electric field, achieving intrinsic spin splitting tunable between 0 and 20 meV. Unexpectedly, α could be enhanced by an order of magnitude in some devices, suggesting that SOC can be further manipulated. Our work highlights the extraordinary tunability of SOC in 2D materials, which can be harnessed for in operando spintronic and topological devices and applications.
自旋轨道耦合（SOC）是一种相对论效应，在这种效应中，在电场中运动的电子在其静止参考系中会经历一个有效磁场。在没有反演对称性的晶体中，它会解除自旋简并，并导致许多磁学、自旋电子学和拓扑学现象及应用。在块体材料中，SOC强度是一个常数。在此，我们展示了原子级厚度的InSe中的SOC和本征自旋分裂，其可以在很宽的范围内被调节。通过量子振荡，我们确定SOC参数α与厚度有关；它可以通过面外电场连续调制，实现0到20毫电子伏特之间的本征自旋分裂可调谐。出乎意料的是，在一些器件中α可以增强一个数量级，这表明SOC可以被进一步操控。我们的工作突出了二维材料中SOC的非凡可调谐性，这可用于原位自旋电子学和拓扑器件及应用。
