Rolled-up architectures for magnetic racetrack memory applications

点击翻译按钮获取中文摘要

Novel properties originating from the combination of magnetism with a reduced dimensionality are of considerable interest for fundamental science but are also of potential interest in technological applications. In this project, we aim to study the effect of curvature of the cylindrical surface on the types of magnetic domain walls as well as their dynamics in thin magnetic films with in-plane and out-of-plane easy axis of magnetization. For this purpose, two systems will be investigated: (i) magnetic films grown onto curved surfaces of nonmagnetic rolled-up tubes of different length and diameter and (ii) ferromagnetic films rolledup in a tubular geometry. The effect of curvature is expected to result in a substantial modification of the magnetization reversal behavior compared to the films grown on planar substrates. The ultimate goal is to determine the velocity of the magnetic domain walls, which is a crucial parameter for applicability of the considered system in a magnetic storage scheme known as “racetrack memory”. Therefore, investigation of field- and current-driven propagation of magnetic domain walls will be performed and correlated to the curvature of the rolled-up tubes. As a layer with an in-plane magnetic easy axis, Fe19Ni81 alloy films with excellent soft magnetic properties will be employed. Furthermore, Co/Pt multilayer stacks were chosen as a system with out-of-plane magnetic easy axis.