Domain Wall Spin Structures and Dynamics Probed by Synchrotron Techniques

Magnetic anisotropies in epitaxial Fe3O4/GaAs(100) patterned structures

“…2, are shown in Fig. 3, where we find that the zig-zag domain walls, as a consequence of the strong fourfold in-plane magnetocrystalline anisotropy of the film in the previous studies, 17 can be avoided in both rings and far more simplified domain structures 16,17 are revealed. Specifically, when being saturated along the hard axis ([011]), followed by relaxation at zero field, our 1-µm-wide Fe 3 O 4 ring exhibits four 180…”

“…15 This is in part attributed to the formation of undesirable domain structures that could result from an interplay between the shape-and the intrinsic cubic magnetocrystalline anisotropies in Fe 3 O 4 . 16 For instance, using x-ray photoemission electron microscopy, Fonin et al observed the appearance of zig-zag shaped domain walls in their 1-µm-wide Fe 3 O 4 rings, 17 as a consequence of the dominant in-plane cubic magnetic anisotropy in the ferrite structures. These zigzag domain walls, with complex wall structure and boundary, could possibly complicate the wall motion, which are certainly setbacks for integrating highly spin-polarized In this Letter, we report a viable approach to circumvent the above-mentioned complication by taking advantage of a unique in-plane magnetic anisotropy system in high-quality Fe 3 O 4 ultrathin film grown on GaAs(100) by postgrowth oxidation of epitaxial Fe(100).…”

“…The ring shape was chosen for its high geometry symmetry, guaranteeing the ease of trapping magnetic domain walls by applying an external magnetic field, [42][43][44] and also for ease of comparison to the previous reports. 16,17 The simulation results, by taking the parameters used for Fig. 2, are shown in Fig.…”