title: Modulated Magnetic Nanowires for Controlling Domain Wall Motion: Toward 3D Magnetic Memories.
abstract: Cylindrical magnetic nanowires are attractive materials for next generation data storage devices owing to the theoretically achievable high domain wall velocity and their efficient fabrication in highly dense arrays. In order to obtain control over domain wall motion, reliable and well-defined pinning sites are required. Here, we show that modulated nanowires consisting of alternating nickel and cobalt sections facilitate efficient domain wall pinning at the interfaces of those sections. By combining electron holography with micromagnetic simulations, the pinning effect can be explained by the interaction of the stray fields generated at the interface and the domain wall. Utilizing a modified differential phase contrast imaging, we visualized the pinned domain wall with a high resolution, revealing its three-dimensional vortex structure with the previously predicted Bloch point at its center. These findings suggest the potential of modulated nanowires for the development of high-density, three-dimensional data storage devices.
authors.affiliation: King Abdullah University of Science and Technology , Thuwal 23955, Saudi Arabia.
authors.forename: Yurii P
authors.initials: YP
authors.lastname: Ivanov
authors.affiliation: CIC nanoGUNE Consolider , Avenida de Tolosa 76, 20018 San Sebastian, Spain.|IKERBASQUE, Basque Foundation for Science , Maria Diaz de Haro 3, 48013 Bilbao, Spain.
authors.forename: Andrey
authors.initials: A
authors.lastname: Chuvilin
authors.affiliation: King Abdullah University of Science and Technology , Thuwal 23955, Saudi Arabia.
authors.forename: Sergei
authors.initials: S
authors.lastname: Lopatin
authors.affiliation: King Abdullah University of Science and Technology , Thuwal 23955, Saudi Arabia.
authors.forename: Jurgen
authors.initials: J
authors.lastname: Kosel
keywords: 3D memory; assembled nanostructures; domain wall motion; electron holography; nanowires