Electrical control of 2D magnetism in bilayer CrI3
Electrical control of 2D magnetism in bilayer CrI3
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DOI：
10.1038/s41565-018-0121-3
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发表时间：
2018-07-01
影响因子：
38.3
通讯作者：
Xu, Xiaodong
中科院分区：
文献类型：
--
作者：
Huang, Bevin;Clark, Genevieve;Xu, Xiaodong
通过电场控制磁性解决了磁现象和相变的基本问题（1-3），并使电耦合自旋电子器件的发展成为可能，例如具有低操作能量的压控磁性存储器（4-6）。以前对稀磁半导体如（Ga，Mn）As和（In，Mn）Sb的研究表明，通过改变磁各向异性和交换相互作用，居里温度和矫顽场会发生很大的调制（2，4，7 -9）。由于其独特的磁性（10-14），最近报道的二维磁体提供了一个新的系统来研究这些功能（15-19）。例如，三碘化铬（CrI 3）的双层表现为具有磁场驱动的变磁转变的层状反铁磁体（15，16）。在这里，我们证明了静电门控制的磁性CrI 3双层，探测磁光克尔效应（MOKE）显微镜。在变磁转变附近的固定磁场下，我们实现了反铁磁态和铁磁态之间的电压控制开关。在零磁场下，我们展示了一对时间反转的分层反铁磁状态，表现出自旋层锁定，导致其MOKE信号对栅极电压的线性依赖性与相反的斜率。我们的研究结果允许新的磁电现象和货车范德华自旋电子学的基础上的二维材料的探索。
Controlling magnetism via electric fields addresses fundamental questions of magnetic phenomena and phase transitions(1-3), and enables the development of electrically coupled spintronic devices, such as voltage-controlled magnetic memories with low operation energy(4-6). Previous studies on dilute magnetic semiconductors such as (Ga, Mn) As and (In, Mn) Sb have demonstrated large modulations of the Curie temperatures and coercive fields by altering the magnetic anisotropy and exchange interaction(2,4,7-9). Owing to their unique magnetic properties(10-14), the recently reported two-dimensional magnets provide a new system for studying these features(15-19). For instance, a bilayer of chromium triiodide (CrI3) behaves as a layered antiferromagnet with a magnetic field-driven metamagnetic transition(15,16). Here, we demonstrate electrostatic gate control of magnetism in CrI3 bilayers, probed by magneto-optical Kerr effect (MOKE) microscopy. At fixed magnetic fields near the metamagnetic transition, we realize voltage-controlled switching between antiferromagnetic and ferromagnetic states. At zero magnetic field, we demonstrate a time-reversal pair of layered antiferromagnetic states that exhibit spin-layer locking, leading to a linear dependence of their MOKE signals on gate voltage with opposite slopes. Our results allow for the exploration of new magnetoelectric phenomena and van der Waals spintronics based on 2D materials.