Strain-driven radial vortex core reversal in geometric confined multiferroic heterostructures

作者：Mingmin Zhu, Huimin Hu, Shuting Cui, Yiting Li, Xiuping Zhou, Yang Qiu, Rongdi Guo, Guohua Wu, Guoliang Yu, Hao-Miao Zhou · 发表于：Applied Physics Letters · 年份：2021 · DOI：10.1063/5.0054010 · 被引用次数：15 · 研究领域：Magnetic properties of thin films、Multiferroics and related materials、Magnetic and transport properties of perovskites and related materials

The magnetic radial vortex is a nanoscale magnetization configuration that is typically stabilized by the interfacial Dzyaloshinskii–Moriya interaction (i-DMI). The existing control methods for the radial vortex core polarity rely on the use of current flow or magnetic fields, which may cause long consumption times or limit device miniaturization. Here, we investigate a repeated reversal of a radial vortex that can be driven by strain from a piezoelectric substrate using micromagnetic simulations. A phase diagram for the representative regions against perpendicular anisotropy, i-DMI, and the applied strain was obtained. The derived phase diagram was used to associate the mechanism of the core reversal with edge magnetization rotation during core magnetization switching, which exhibits a relationship by transforming a quasi-Bloch wall into a Néel wall. The existence of the i-DMI effect causes the core polarity and radial chirality of the radial vortex to be reversed simultaneously without resulting in larger core movements. These results offer an alternative and efficient way to achieve core reversal, which is expected to stimulate the radial vortex application in magnetoresistive memory devices.