Ohuchi Yuki, Matsuno Jobu, Ogawa Naoki, Kozuka Yusuke, Uchida Masaki, Tokura Yoshinori, Kawasaki Masashi
Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), University of Tokyo, Tokyo, 113-8656, Japan.
RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama, 351-0198, Japan.
Nat Commun. 2018 Jan 15;9(1):213. doi: 10.1038/s41467-017-02629-3.
One of the key goals in spintronics is to tame the spin-orbit coupling (SOC) that links spin and motion of electrons, giving rise to intriguing magneto-transport properties in itinerant magnets. Prominent examples of such SOC-based phenomena are the anomalous and topological Hall effects. However, controlling them with electric fields has remained unachieved since an electric field tends to be screened in itinerant magnets. Here we demonstrate that both anomalous and topological Hall effects can be modulated by electric fields in oxide heterostructures consisting of ferromagnetic SrRuO and nonmagnetic SrIrO. We observe a clear electric field effect only when SrIrO is inserted between SrRuO and a gate dielectric. Our results establish that strong SOC of nonmagnetic materials such as SrIrO is essential in electrical tuning of these Hall effects and possibly other SOC-related phenomena.
自旋电子学的关键目标之一是控制自旋轨道耦合（SOC），这种耦合将电子的自旋与运动联系起来，在巡游磁体中产生引人入胜的磁输运特性。这种基于SOC的现象的突出例子是反常霍尔效应和拓扑霍尔效应。然而，由于电场在巡游磁体中往往会被屏蔽，因此用电场控制这些效应一直未能实现。在此，我们证明，在由铁磁体SrRuO和非磁体SrIrO组成的氧化物异质结构中，反常霍尔效应和拓扑霍尔效应都可以通过电场进行调制。我们发现，只有当SrIrO插入到SrRuO和栅极电介质之间时，才会观察到明显的电场效应。我们的结果表明，诸如SrIrO等非磁性材料的强SOC对于这些霍尔效应以及可能的其他与SOC相关的现象的电调谐至关重要。
