Electric Field-Induced Creation and Directional Motion of Domain Walls and Skyrmion Bubbles

Magnetization dynamics driven by an electric field could provide long-term benefits to information technologies because of its ultralow power consumption. Meanwhile, the Dzyaloshinskii-Moriya interaction in interfacially asymmetric multilayers consisting of ferromagnetic and heavy-metal layers can stabilize topological spin textures, such as chiral domain walls, skyrmions, and skyrmion bubbles. These topological spin textures can be controlled by an electric field and hold promise for building advanced spintronic devices. Here, we present an experimental and numerical study on the electric field-induced creation and directional motion of topological spin textures in magnetic multilayer films and racetracks with thickness gradient and interfacial Dzyaloshinskii-Moriya interaction at room temperature. We find that the electric field-induced directional motion of chiral domain wall is accompanied by the creation of skyrmion bubbles at certain conditions. We also demonstrate that the electric field variation can induce motion of skyrmion bubbles. Our findings may provide opportunities for developing skyrmion-based devices with ultralow power consumption.电场驱动的磁化动力学凭借超低功耗特性，可为信息技术领域带来长期的应用价值。与此同时，由铁磁层与重金属层构成的界面不对称多层膜中存在的Dzyaloshinskii-Moriya相互作用（Dzyaloshinskii-Moriya interaction），可稳定手性畴壁、斯格明子（skyrmions、斯格明子泡等拓扑自旋纹理。此类拓扑自旋纹理可通过电场调控，在构建先进自旋电子学器件方面具有重要应用前景。本研究针对室温下具备厚度梯度与界面Dzyaloshinskii-Moriya相互作用的磁性多层膜与磁赛道中拓扑自旋纹理的电场诱导生成与定向运动，开展了实验与数值模拟研究。我们发现，在特定条件下，手性畴壁的电场诱导定向运动过程中会伴随斯格明子泡的生成。同时，电场变化亦可诱导斯格明子泡发生运动。本研究成果可为开发超低功耗的斯格明子基器件提供新的发展机遇。