Probing and tuning the atomistic antisymmetric exchange interaction at interfaces

探测和调整界面处的原子反对称交换相互作用

• 批准号: 464601172
• 负责人: Privatdozent Dr. Khalil Zakeri Lori
• 金额: --
• 依托单位: Physikalisches Institut (PHI)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/464601172?language=en
• 关键词: Probing; tuning; atomistic; antisymmetric; exchange

The properties of magnetic solids are governed by the interplay between different microscopic magnetic interactions, i.e., symmetric Heisenberg exchange interaction, antisymmetric Dzyaloshiskii-Moriya interaction (DMI), dipolar interactions, biquadratic interactions, magnetic anisotropy, etc. Owing to its antisymmetric nature, DMI can stabilize topologically protected spin textures, having a unique rotation sense. Examples are spin spirals, spin helixes, skyrmions and antiskyrmions. These are magnetic whirls with a well-defined topological charge. The most important property of theseobjects is that they couple efficiently to spin currents and show a great potential to be used as information storage in future ultrahigh-density, and energy-efficient spin-based logic devices.In this project, we aim to tailor the DMI in magnetic thin films and multilayers. The main objective of the project is twofold. First, we would like to tune the DMI by introducing an additional structural asymmetry in the atomic bilayers made of ferromagnetic materials grown on heavy metal substrates. We will examine different bilayers on W(110) and Ir(111) surfaces. Both the Heisenberg exchange and the DMI will be probed by magnon spectroscopy. Second, we will introduce an additional asymmetry in these systems by adding a monolayer of a heavy metal e.g., Pt on top of these structures and investigate the influence of the additional interface. A complete investigation of all these systems would allow us to understand the fundamental details of the symmetric and antisymmetric magnetic interactions and, in the next step, would enable us to provide guidelines for quantum engineering of these interactions on the atomic length-scales. Such a knowledge is essential to design magnetic multilayers and superlattices, which show specific properties or can host exotic topological spin textures.

磁性固体的性质由不同微观磁性相互作用之间的相互作用决定，即，对称海森堡交换相互作用、反对称Dzyaloshiskii-Moriya相互作用（Dzyaloshiskii-Moriya interaction）、偶极相互作用、双二次相互作用、磁各向异性等。由于其反对称性质，Dzyaloshiski-Moriya相互作用可以稳定拓扑保护的自旋织构，具有独特的旋转方向。例子是自旋螺旋，自旋螺旋，skyrmions和antiskyrmions。这些是具有明确拓扑电荷的磁旋。这些材料最重要的特性是它们能有效地与自旋电流耦合，在未来超高密度、高能效的自旋逻辑器件中显示出巨大的信息存储潜力。该项目的主要目标有两个。首先，我们想通过在重金属衬底上生长的铁磁材料制成的原子双层中引入额外的结构不对称性来调整介电常数。我们将研究W（110）和Ir（111）表面上的不同双层。海森伯交换和磁振子都将用磁振子光谱学来探测。第二，我们将通过添加重金属单层在这些系统中引入额外的不对称性，例如，Pt在这些结构的顶部，并研究额外的接口的影响。对所有这些系统的全面研究将使我们能够理解对称和反对称磁相互作用的基本细节，并且在下一步中，将使我们能够为原子长度尺度上这些相互作用的量子工程提供指导。这样的知识是必不可少的设计磁性多层膜和超晶格，表现出特定的属性或可以主机奇异的拓扑自旋纹理。