Institute for Metallic Materials, IFW Dresden, Helmholtzstr. 20, 01069 Dresden, Germany.
Institut für Festkörper- und Materialphysik, Technische Universität Dresden, 01062 Dresden, Germany.
Phys Rev Lett. 2018 May 25;120(21):217201. doi: 10.1103/PhysRevLett.120.217201.
Envisaged applications of Skyrmions in magnetic memory and logic devices crucially depend on the stability and mobility of these topologically nontrivial magnetic textures in thin films. We present for the first time quantitative maps of the magnetic induction that provide evidence for a 3D modulation of the Skyrmionic spin texture. The projected in-plane magnetic induction maps as determined from in-line and off-axis electron holography carry the clear signature of Bloch Skyrmions. However, the magnitude of this induction is much smaller than the values expected for homogeneous Bloch Skyrmions that extend throughout the thickness of the film. This finding can only be understood if the underlying spin textures are modulated along the out-of-plane z direction. The projection of (the in-plane magnetic induction of) helices is further found to exhibit thickness-dependent lateral shifts, which show that this z modulation is accompanied by an (in-plane) modulation along the x and y directions.
斯格明子在磁存储和逻辑器件中的预期应用，关键取决于这些拓扑非平凡磁织构在薄膜中的稳定性和迁移率。我们首次提供了磁感应的定量图谱，这些图谱为斯格明子自旋织构的三维调制提供了证据。从线内和离轴电子全息术确定的平面内投影磁感应图谱具有布洛赫斯格明子的清晰特征。然而，这个感应的幅度比预期的贯穿整个薄膜厚度的均匀布洛赫斯格明子的感应小得多。如果底层自旋织构沿垂直于薄膜的 z 方向调制，那么只能这样解释。进一步发现螺旋的（平面内磁感应的）投影表现出与厚度相关的横向位移，这表明这种 z 调制伴随着沿 x 和 y 方向的（平面内）调制。
