Surface Properties of New Complex Metallic Alloys

复杂金属合金(CMA)包括一个广泛的化合物家族，其特点是其大的单位晶胞和它们的组成与单位晶胞中的原子簇。其结果是CMA的物理性能与传统金属合金相比是独一无二的。尤其令人感兴趣的是准晶(QC)，其大的晶胞和非周期晶体结构被发现具有独特的性能组合，具有摩擦学应用以及低导电性和潜在的低成本。尽管QC不具有平移对称性，但QC表现出周期晶体中被禁止的旋转对称性，例如5倍、10倍和12倍的旋转对称性，这需要比空间维度更多的基矢来描述倒易空间中的QC。本研究项目有两个感兴趣的领域：(I)我们将通过原子和分子在准周期衬底上的吸附来生成新的QC纳米结构，并探索它们的结构和电子性质。我们建议使用二十面体准晶的三重表面作为衬底来沉积C60或并五苯等分子，形成金属薄膜。这些薄膜将用扫描隧道显微镜(STM)、低能电子衍射(LEED)和X射线光电子能谱(XPS)进行表征。(Ii)我们将使用纳米光刻技术产生亚微米级的准周期瓷砖，特别是用扫描电子显微镜(SEM)、磁力显微镜(MFM)和原子力显微镜(AFM)研究它们的结构和磁性。这项研究的总体目标是了解QC的电子和磁性，以供技术应用。

Complex Metallic Alloys (CMA) comprise a broad family of compounds, characterised by their large unit cells and their composition with clusters of atoms in the unit cell. The result of this is the physical properties of CMA are unique with respect to conventional metal alloys. Of particular interest are quasicrystals (QC), whose large unit cells and aperiodic crystalline structures have been found to have a unique combination of properties, with tribological applications as well as low conductivity and potential low cost. Although they have no translational symmetry, QC exhibit rotational symmetry forbidden in periodic crystals, such as 5, 10 and 12-fold rotational symmetry that require a higher number of basis vectors than spatial dimensions to describe the QC in reciprocal space.This research project has two areas of interest: (i) we will generate new QC nanostructures through atomic and molecular adsorption on quasiperiodic substrates and explore their structural and electronic properties. We propose to deposit molecules such as C60 or Pentacene using 3-fold surfaces of icosahedral quasicrystals as substrates, forming metallic thin film layers. These layers will be characterised with scanning tunnel microscopy (STM), low energy electron diffraction (LEED) and X-ray photoelectron spectroscopy (XPS). (ii) We will generate quasiperiodic tilings of sub-micron scale using nanolithography, and in particular investigate their structure and magnetic properties with scanning electron microscopy (SEM), magnetic force microscopy (MFM) and atomic force microscopy (AFM). The overall objective of this research is to understand electronic and magnetic properties of QC for technological applications.