论文标题
拓扑厅效应和在电荷转移界面处类似天空的气泡
Topological Hall Effect and Skyrmion-like Bubbles at a Charge-transfer Interface
论文作者
论文摘要
探索由于电荷转移和强旋转轨道耦合而引起的外来界面磁性在未来的旋转记忆中具有深刻的应用。在这里，详细研究了CAMNO3/CAIRO3/CAMNO3三层结构的驼峰形厅效应的出现，调整和解释。驼峰信号可以识别为拓扑厅效应，表明存在类似天空的磁性气泡。但是，还讨论了辩论的替代解释，其中还讨论了两个取消异常霍尔效应循环之间的人工制品。首先，通过倾斜磁场方向，霍尔信号的演变表明气泡拓扑转化为更琐碎的类型。其次，通过改变CAMNO3的厚度，发现了驼峰信号出现的最佳厚度，这表明对电荷转移分数进行调整。使用高分辨率透射电子显微镜，还确定了堆叠断层，从电荷转移分数和可能的界面dzyaloshinskii-Moriya相互作用方面，可以区分顶部和底部CAMNO3/CAIRO3接口。最后，一个自旋转移扭矩实验显示，用于启动气泡运动的低阈值电流密度为〜10^9 a/m^2。这一发现为将天空与抗磁性旋转旋转的融合开设了可能的途径。
Exploring exotic interface magnetism due to charge transfer and strong spin-orbit coupling has profound application in future development of spintronic memory. Here, the emergence, tuning and interpretation of hump-shape Hall Effect from a CaMnO3/CaIrO3/CaMnO3 trilayer structure are studied in detail. The hump signal can be recognized as Topological Hall Effect suggesting the presence of Skyrmion-like magnetic bubbles; but the debated alternative interpretation where the signal being an artefact between two cancelling Anomalous Hall Effect loops is also discussed. Firstly, by tilting the magnetic field direction, the evolution of Hall signal suggests transformation of the bubbles topology into a more trivial kind. Secondly, by varying the thickness of CaMnO3, the optimal thicknesses for the hump signal emergence are found, suggesting a tuning of charge transfer fraction. Using high-resolution transmission electron microscopy, a stacking fault is also identified, which distinguishes the top and bottom CaMnO3/CaIrO3 interfaces in terms of charge transfer fraction and possible interfacial Dzyaloshinskii-Moriya Interaction. Finally, a spin-transfer torque experiment revealed a low threshold current density of ~10^9 A/m^2 for initiating the motion of bubbles. This discovery opens a possible route for integrating Skyrmions with antiferromagnetic spintronics.
