Homochiral Magnetic Structures in Deposited Clusters

沉积团簇中的同手性磁性结构

• 批准号: 45039306
• 负责人: Professor Dr. Stefan Blügel
• 金额: --
• 依托单位: PGI-1 / IAS-1: Quanten-Theorie der Materialien
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2007
• 资助国家: 德国
• 起止时间: 2006-12-31 至 2009-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/45039306?language=en
• 关键词: Homochiral; Magnetic; Structures; Deposited; Clusters

The unique homochirality of biopolymers and the parity violation of the electroweak interaction are two fascinating examples where the laws of nature are different for an image and for a mirror image. We believe this is also true for the magnetic structure in metal clusters deposited on surfaces. We propose the investigation of the existence and the strength of the Dzyaloshinskii- Moriya (DM) interaction of preferably ferromagnetic clusters, e.g. Fe, Co, Ni, Ru, and Os, deposited on substrates with large nuclear numbers, e.g. W, Ir, Pt, Pb, or Bi. We argue that during the past 20 years of ab initio calculations on the magnetism of small magnetic objects deposited on substrates, magnetism has only been explained on the basis of the symmetric Heisenberg exchange and the magnetic (uniaxial) anisotropy, while the DM interaction had been either overlooked, ignored or forgotten. We will implement an approach to calculate the strength of DM interaction, the DM-vector D, based on the idea of infinitesimal rotations, in a relativistic Korringa-Kohn-Rostoker Green function (KKR-GF) method based on the density functional theory. We will prove that the strength of the DM interaction is sufficient to compete with the other interactions to produce homochiral magnetic structures. Since the DM vector D depends decisively on the symmetry of the system, clusters provide a particularly fruitful field for such studies.

生物聚合物的独特的同手性和电弱相互作用的宇称违反是两个有趣的例子，说明自然定律对于像和镜像是不同的。我们相信这也适用于沉积在表面的金属团簇中的磁性结构。我们建议研究在W、Ir、Pt、Pb或Bi等核数较大的衬底上沉积的铁磁团簇（如Fe、Co、Ni、Ru和Os）的Dzyaloshinskii- Moriya （DM）相互作用的存在和强度。我们认为，在过去20年对沉积在衬底上的小磁性物体的磁性的从头计算中，磁性仅在对称海森堡交换和磁性（单轴）各向异性的基础上得到解释，而DM相互作用要么被忽视，要么被忽略或遗忘。我们将在基于密度泛函理论的相对论Korringa-Kohn-Rostoker Green函数（KKR-GF）方法中实现一种基于无穷小旋转思想的DM-矢量D计算DM相互作用强度的方法。我们将证明DM相互作用的强度足以与其他相互作用竞争产生同手性磁结构。由于DM向量D决定性地依赖于系统的对称性，因此聚类为这类研究提供了一个特别富有成果的领域。