Figure 2. Fabrication and characterization of circulating spin textures.

(a) Preparation of azimuthally magnetized tubular architectures via selective rolling up of a prepatterned strained nanomembrane with transverse magnetic easy axis (indicated by red and blue, and arrows). (b) Electron micrographs of rolled-up tubes and manipulation. Scale bar, 50 μm. (c) Transverse magnetization component along a 2-μm wide stripe at the very top of the tube visualized by longitudinal Kerr microscopy. Scale bar, 5 μm. (d) Electron micrograph of a vertically fixed Ni tube with circulating magnetization overlaid with XMCD shadow contrast patterns recored by T-XPEEM at various projection angles. The X-ray beam penetrates the top end of the standing tube (dashed rectangle) and projects the magnetization onto the substrate 150 μm away from the tube location (indicated by wiggly lines). The lengths of major and minor axis are x=(8.4±0.2) μm and y=(5.5±0.2) μm, respectively. Scale bar, 5 μm. (e) Magnetic hysteresis loops of planar (dashed) and rolled-up (solid) nanomembranes shown for longitudinal and transverse sensitivity suggest circulating (azimuthal or helical) magnetization within the rolled-up nanomembrane.