Magnetism of size selected, deposited transition metal and alloy clusters

选定尺寸、沉积的过渡金属和合金簇的磁性

• 批准号: 5455450
• 负责人: Professor Dr. Kai Fauth
• 金额: --
• 依托单位: Lehrstuhl für Experimentelle Physik IV
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2005
• 资助国家: 德国
• 起止时间: 2004-12-31 至 2009-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5455450?language=en
• 关键词: Magnetism; size; selected; deposited; transition

Clusters may experience strong modifications with respect to their intrinsic properties when being in contact with a surface. Electronic structure relaxation may particularly modify the magnetic moments in transition metal clusters, since they are directly connected with the electronic configuration of the open 3d shell. In addition, the interaction with the substrate may lead to an effective magnetic cluster cluster interaction, giving rise to super-ferromagnetism. The experiment proposed here are concerned with these two specific aspects of interactions between mass selected magnetic clusters and solid surfaces. The high sensitivity of x-ray magnetic circular dichroism will be exploited to study the magnetic properties clusters deposited in situ. The evolution of the magnetic moments in binary alloy (FePt,CoPt) clusters will be studied as a function of atomic composition, which can be precisely chosen by mass selection at small cluster sizes. Likewise, the effect of alloying on the magnetic sensitivity to surface interaction will be specifically studied. Effective magnetic cluster cluster interactions will be studied for the system Fen/Cu(111) to elucidate the mechanism behind the high critical temperatures and strong magnetic anisotropies reported for this class of systems. Here, we will explore both, the dependence on particle size and the preparation method (cluster deposition versus cluster formation in rare gas layers), respectively.

当与表面接触时，簇可经历关于其固有性质的强烈改变。电子结构弛豫可以特别地改变过渡金属簇中的磁矩，因为它们与开放的3d壳层的电子构型直接相关。此外，与衬底的相互作用可能导致有效的磁性团簇相互作用，从而产生超铁磁性。这里提出的实验涉及质量选择磁性团簇与固体表面之间相互作用的这两个具体方面。利用x射线磁性圆二色性的高灵敏度，研究了原位沉积的团簇的磁性。二元合金（FePt，CoPt）团簇的磁矩的演变将被研究作为原子组成的函数，这可以精确地选择在小的簇尺寸的质量选择。同样，合金化对表面相互作用的磁敏感性的影响将被专门研究。我们将研究Fen/Cu（111）系统的有效磁团簇相互作用，以阐明这类系统的高临界温度和强磁各向异性背后的机制。在这里，我们将探讨这两个，对颗粒大小和制备方法（集群沉积与集群形成在稀有气体层）的依赖，分别。