Spin relaxation and spin coherence in nonmagnetic metallic ultrathin films and nanowires.

非磁性金属超薄膜和纳米线中的自旋弛豫和自旋相干。

• 批准号: 170692815
• 负责人: Professor Dr. Yuriy Mokrousov
• 金额: --
• 依托单位: Institut für Physik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2010
• 资助国家: 德国
• 起止时间: 2009-12-31 至 2013-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/170692815?language=en
• 关键词: Spin; relaxation; spin; coherence; nonmagnetic

In the field of spintronics, there is a vision of information transfer by spin-polarized currents through non-magnetic materials. In any material, however, dissipation of spin currents leads to spin relaxation and loss of information. The corresponding spin relaxation rate depends on intrinsic and extrinsic factors, such as point defects, crystal surfaces, lattice vibrations, etc., which all together contribute to spin-flip scattering via the effect of spin-orbit coupling (SOC). We aim at an understanding and quantitative prediction of these phenomena, with special focus on thin and ultra-thin metallic films that are commonly used in experimental spintronics devices, but also in nanowires where the reduced dimensionality can lead to surprising new physics. We wish to understand how spin relaxation is affected by the sample-dependent electronic structure, such as surface states, scattering at the substrate, or impurities that occur during sample preparation. We want to compare the effect of scattering at point defects to that of phonons, and to see if the Elliott-Yafet type of relaxation is dominant, or if the Dyakonov- Perel mechanism for spin decoherence can be also important. Finally we want to see if the reduced dimensionality can partly suppress spin relaxation even in the presence of strong spin-orbit coupling, in view of the importance of the latter for the spin-Hall effect.

在自旋电子学领域，有一种通过非磁性材料的自旋极化电流进行信息传输的设想。然而，在任何材料中，自旋电流的耗散都会导致自旋弛豫和信息丢失。相应的自旋弛豫速率取决于内在和外在因素，例如点缺陷、晶体表面、晶格振动等，它们通过自旋-轨道耦合（SOC）的效应一起促成自旋翻转散射。我们的目标是理解和定量预测这些现象，特别关注通常用于实验自旋电子器件的薄和超薄金属薄膜，以及纳米线，其中降低的维度可以导致令人惊讶的新物理。我们希望了解自旋弛豫是如何影响样品依赖的电子结构，如表面状态，在基板上的散射，或在样品制备过程中发生的杂质。我们想比较点缺陷处的散射效应与声子的散射效应，看看埃利奥特-雅菲型弛豫是否占主导地位，或者迪雅科诺夫-佩雷尔自旋退相干机制是否也很重要。最后，我们想看看，如果减少维数可以部分抑制自旋弛豫，即使在存在强自旋轨道耦合，鉴于后者的重要性的自旋霍尔效应。

项目成果

Anisotropy of spin relaxation in metals.

• DOI: 10.1103/physrevlett.109.236603
• 发表时间: 2012-10
• 期刊: Physical review letters
• 影响因子: 8.6
• 作者: B. Zimmermann;P. Mavropoulos;S. Heers;N. H. Long;S. Blügel;Y. Mokrousov

Anisotropy of spin relaxation and transverse transport in metals

• DOI: 10.1088/0953-8984/25/16/163201
• 发表时间: 2012-06
• 期刊: Journal of Physics: Condensed Matter
• 作者: Y. Mokrousov;Hongbin Zhang;F. Freimuth;B. Zimmermann;N. H. Long;J. Weischenberg;Ivo Souza;P. Mavropoulo

Spin relaxation and spin Hall transport in 5d transition-metal ultrathin films

• DOI: 10.1103/physrevb.90.064406
• 发表时间: 2014-05
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: N. H. Long;P. Mavropoulos;B. Zimmermann;D. Bauer;S. Blugel;Y. Mokrousov

Spin relaxation and the Elliott-Yafet parameter in W(001) ultrathin films: Surface states, anisotropy, and oscillation effects

W(001) 超薄膜中的自旋弛豫和 Elliott-Yafet 参数：表面态、各向异性和振荡效应

• DOI: 10.1103/physrevb.87.224420
• 发表时间: 2013
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: N. H. Long;P. Mavropoulos;S. Heers;B. Zimmermann;D. S. G. Bauer;S. Blügel;Y. Mokrousov
• 通讯作者: Y. Mokrousov

Spin-flip hot spots in ultrathin films of monovalent metals: Enhancement and anisotropy of the Elliott-Yafet parameter

单价金属超薄膜中的自旋翻转热点：Elliott-Yafet 参数的增强和各向异性

• DOI: 10.1103/physrevb.88.144408
• 发表时间: 2013
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: N. H. Long;P. Mavropoulos;S. Heers;B. Zimmermann;Y. Mokrousov;S. Blügel
• 通讯作者: S. Blügel