Current-induced magnetization instabilities in thin magnetic films: self-consistent Langevin dynamics simulations

磁性薄膜中电流感应磁化不稳定性：自洽朗之万动力学模拟

• 批准号: 27214628
• 负责人: Privatdozent Dr. Dmitry Berkov
• 金额: --
• 依托单位: General Numerics Research Lab e.V.
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2006
• 资助国家: 德国
• 起止时间: 2005-12-31 至 2007-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/27214628?language=en
• 关键词: Current; induced; magnetization; instabilities; thin

The main goal of this project a qualitative improvement of our theoretical understanding of the interaction between an electric current and a magnetization of a ferromagnetic film due to the spin-transfer phenomena. According to recent theoretical predictions, already a nonpolarized current (i.e., a current without a net spin polarization) flowing through a ferromagnetic layer can induce instabilities of its magnetization configuration, causing the appearance of magnetization excitations and switching. We intend to include the magnetization-dependent spin accumulation accompanied by a spin-diffusion (which is supposed to be the mechanism responsible for these instabilities) into the full-scale micromagnetic simulations of the spin-transfer phenomena. As a result of taking into account this qualitatively new effect we expect a decisively better understanding of the spin-transfer induced magnetization dynamics in structures with experimentally relevant sizes, where the formation of complicated mesoscopic domain patterns should be taken into account. From the point of view of potential applications results of this project should be of a great interest, helping to establish optimal conditions for switching and steady-state precession of a nanoelement magnetization induced by a spin-polarized and unpolarized currents.

本计画的主要目的是从质上增进我们对于铁磁薄膜中电流与磁化强度间因自旋转移现象而产生的相互作用的理论了解。根据最近的理论预测，已经有非极化电流（即，没有净自旋极化的电流）流过铁磁层，可以引起其磁化结构的不稳定性，导致磁化激励和切换的出现。我们打算包括磁化相关的自旋积累伴随着自旋扩散（这应该是负责这些不稳定性的机制）到自旋转移现象的全尺度微磁模拟。由于考虑到这种定性的新效果，我们期望一个决定性的更好地了解自旋转移诱导的磁化动力学的结构与实验相关的大小，其中复杂的介观域图案的形成应考虑在内。从潜在应用的角度来看，该项目的结果应该是一个很大的兴趣，有助于建立最佳条件的开关和稳态旋进的纳米元素磁化诱导的自旋极化和非极化电流。