Magnetic skyrmions-bubble hybrids in nanolayers of metallic ferromagnets: interplay of the magnetodipolar and Dzyaloshinskii-Moriya interactions

金属铁磁体纳米层中的磁性斯格明子-气泡杂化物：磁偶极和 Dzyaloshinskii-Moriya 相互作用的相互作用

• 批准号: 403039150
• 负责人: Professor Dr. Alexei N. Bogdanov
• 金额: --
• 依托单位: Institut für Theoretische Festkörperphysik
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/403039150?language=en
• 关键词: Magnetic; skyrmions; bubble; hybrids; nanolayers

Axisymmetric solitons stabilized by intrinsic and/or induced Dzyaloshinskii-Moriya (DM) interactions (chiral skyrmions) and common cylindrical magnetic domains (bubbles) stabilized by surface demagnetization effects are two fundamentally different types of topologically non-trivial magnetic structures observed in recently synthesized nanolayers and multilayer stacks of magnetic compounds. They contain areas of reversed magnetization localized in spots of the nano- to microscale size and thus are considered as promising objects for novel types of magnetic data storage and other applications in emerging spin electronics. Recently, a different kind of localized magnetic patterns – formed under the combined influence of chiral DM and magnetodipolar interactions – has been observed in many types of nanolayers. These specific localized states represent intermediate objects between "pure" chiral skyrmions found in nanolayers of non-centrosymmetric ferromagnets and classical bubble domains arising in ferromagnetic films with strong perpendicular anisotropy. These structures can be considered as "skyrmion-bubble hybrids" exhibiting properties attributed both to chiral skyrmions and magnetic domains. Within this project we shall develop a theory of corresponding localized and modulated states arising in recently synthesized nanomagnetic systems with moderate or weak perpendicular anisotropy and intrinsic and/or induced chiral modulations due to the DM interaction. Analytical theoretical research will be combined with domain observation using high-resolution magneto-optical Kerr microscopy and full-scale advanced micromagnetic simulations. Based on our theoretical and experimental findings we intend to create a comprehensive physical description of the bubble-skyrmion states arising in modern nanomagnetic materials with intrinsic and induced chiral interactions.

通过本征和/或诱导的 Dzyaloshinskii-Moriya (DM) 相互作用（手性斯格明子）稳定的轴对称孤子和通过表面退磁效应稳定的常见圆柱形磁域（气泡）是在最近合成的纳米层中观察到的两种根本不同类型的拓扑非平凡磁结构它们包含位于纳米级到微米级尺寸的斑点中的反向磁化区域，因此被认为是有前途的。最近，在许多类型的纳米层中观察到了在手性 DM 和磁偶极相互作用的综合影响下形成的不同类型的局部磁性图案。这些结构可以代表非中心对称铁磁体纳米层中发现的“纯”手性斯格明子和具有强垂直各向异性的铁磁薄膜中出现的经典气泡域之间的中间物体。被认为是“斯格明子-气泡杂化体”，表现出手性斯格明子和磁域的特性，在这个项目中，我们将开发一种在最近合成的具有中度或弱垂直各向异性和固有和/或垂直各向异性的纳米磁系统中相应的局域和调制产生态的理论。或由于 DM 相互作用而引起的手性调制，分析理论研究将与使用高分辨率磁光克尔显微镜和全尺寸先进的域观察相结合。基于我们的理论和实验结果，我们打算对现代纳米磁性材料中产生的具有内在和诱导手性相互作用的气泡-斯格明子态进行全面的物理描述。