Exploring Oersted field driven domain wall motion in complex 3D nanostructures

This proposal builds on our ongoing effort to establish a fundamental understanding of domain wall (DW) dynamics in complex 3D magnetic nanostructures. Our recent work [1] has shown that domain walls can be controllably pinned in regions of alternating curvature, enabling us to design reproducible DW configurations and magnetic field driven DW motion. In our previous beamtime (AV-2023027436), we demonstrated the successful nucleation and manipulation of Bloch point DWs in this kind of undulating nanowires via short current pulses although high current values were needed. The main novelty of this beamtime is to explore domain wall motion in thicker nanowires, where the Oersted (Oe) field generated by nanosecond current pulses becomes significantly more relevant. In cylindrical nanowires with azimuthal magnetization, the Oe field’s symmetry matches the one of the magnetic configuration, potentially unlocking efficient, low-power DW propagation regimes. This experiment will allow us to clarify the role of the Oe field in such geometries and optimize conditions for deterministic, current-driven motion of domain walls.