Surface magnetic and structural properties studied with metastable de-excitation spectroscopy.

使用亚稳态去激发光谱研究表面磁性和结构特性。

• 批准号: EP/D03471X/1
• 负责人: Chris Binns
• 金额: $ 2.81万
• 依托单位: University of Leicester
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2006
• 资助国家: 英国
• 起止时间: 2006 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FD03471X%2F1
• 关键词: Surface; magnetic; structural; properties; studied

The structure and properties of the topmost atomic layer of a material become increasingly significant when ever smaller amounts of the material are used to make devices. Sometimes the electronic and magnetic properties of the surface can be very different from those of the underlying material, and difficult to predict. This work will answer questions about some material systems which we know are unusual, and we know how to create them, but without a complete understanding of their properties they cannot be fully exploited for technological applications. For example what is the difference in the surface structure of silicon atoms between 2- and 3-Dimensional rare-earth silicides? Do the exceptional magnetic properties of small clusters of atoms originate from the bulk or the surface? We will use a variety of techniques to measure these properties, but in particular metastable de-excitation spectroscopy. In a unique instrument, excited (metastable) helium atoms are focussed onto the surface of interest using laser-cooling methods. Approaching to within a few Angstroms of the surface, the energy of the atoms is released, liberating electrons from the sample with an energy spectrum characteristic of the electronic, structural and magnetic properties of the surface, and not confused by contributions from underlying atoms.

当使用更少量的材料来制造设备时，材料的最顶层原子层的结构和性质变得越来越重要。有时候，表面的电子和磁性可能与底层材料的电子和磁性非常不同，并且难以预测。这项工作将回答一些材料系统的问题，我们知道这些系统是不寻常的，我们知道如何创造它们，但如果没有完全了解它们的特性，它们就不能完全用于技术应用。例如，二维和三维稀土硅化物之间硅原子的表面结构有什么不同？小原子团簇的特殊磁性是源自本体还是表面？我们将使用各种技术来测量这些属性，但特别是亚稳态去激发光谱。在一个独特的仪器中，激发（亚稳态）氦原子使用激光冷却方法聚焦到感兴趣的表面上。在接近表面的几埃内，原子的能量被释放，从样品中释放出具有表面的电子、结构和磁性特性的能谱特征的电子，并且不会被底层原子的贡献所混淆。

项目成果

Surface Spin Polarization of Fe Nanoclusters

Fe 纳米团簇的表面自旋极化

• DOI: 10.1109/tmag.2010.2045482
• 发表时间: 2010
• 期刊: IEEE Transactions on Magnetics
• 影响因子: 2.1
• 作者: Pratt A