Ummelen Fanny, Swagten Henk, Koopmans Bert
Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands.
Sci Rep. 2017 Apr 11;7(1):833. doi: 10.1038/s41598-017-00837-x.
Magnetic domain wall motion could be the key to the next generation of data storage devices, shift registers without mechanically moving parts. Various concepts of such so-called 'racetrack memories' have been developed, but they are usually plagued by the need for high current densities or complex geometrical requirements. We introduce a new device concept, based on the interfacial Dzyaloshinskii-Moriya interaction (DMI), of which the importance in magnetic thin films was recently discovered. In this device the domain walls are moved solely by magnetic fields. Unidirectionality is created utilizing the recent observation that the strength with which a domain wall is pinned at an anisotropy barrier depends on the direction of the in-plane field due to the chiral nature of DMI. We demonstrate proof-of-principle experiments to verify that unidirectional domain-wall motion is achieved and investigate several material stacks for this novel device including a detailed analysis of device performance for consecutive pinning and depinning processes.
磁畴壁运动可能是下一代数据存储设备（即无机械运动部件的移位寄存器）的关键所在。人们已经开发出了各种此类所谓“跑道式存储器”的概念，但它们通常受到高电流密度需求或复杂几何要求的困扰。我们引入了一种基于界面Dzyaloshinskii-Moriya相互作用（DMI）的新设备概念，最近人们发现了这种相互作用在磁性薄膜中的重要性。在这种设备中，畴壁仅由磁场移动。利用最近的一项观察结果来实现单向性，即由于DMI的手征性质，畴壁在各向异性势垒处的钉扎强度取决于面内磁场的方向。我们展示了原理验证实验，以验证实现了单向畴壁运动，并研究了用于这种新型设备的几种材料堆叠结构，包括对连续钉扎和去钉扎过程的设备性能进行详细分析。
