Asymmetrical current-induced domain-wall motion in cylindrical magnetic nanowires with azimuthal magnetization

Magnetic cylindrical nanowires provide an excellent platform for the study of magnetization dynamics in elongated nanosystems and may be the building blocks for the next generation of spintronics devices based on the control of domain wall motion. During a recent beamtime at MISTRAL (2023027482), we successfully demonstrated controlled domain wall motion in cylindrical nanowires driven by the Oersted field at a low current density of 10E10 A/m2. Now, we are interested in exploring the possibility of measuring the unidirectional motion of the domain walls (ratchet effect) by introducing periodic gradients of composition along the length of ferromagnetic nanowires. Together with a detailed study of the magnetic properties and magnetization dynamics using Transmission X-ray Microscopy (TXM), the understanding of the system requires of a detailed study of the composition and structural properties of these nanowires by Transmission Electron Microscopy (TEM). The aim of this proposal is to establish a correlation of the threshold currents for domain wall movement measured by TXM and the local structure and composition of the nanowires, measured in both cases in the same region and nanowire.