Atomic structure and electronic properties of silicide nanowires

本项目主要研究在硅表面形成的稀土和过渡金属硅化物纳米线的原子结构和电子性质。原子结构的特点是使用扫描隧道显微镜，掠入射X射线衍射，低能电子衍射，也与斑点轮廓分析和强度电压分析。角分辨光电子能谱和扫描隧道能谱被应用于研究（本地）电子性质。自组织纳米线形成的两种策略，使用生长的硅化物以及各向异性基板的各向异性应变。在第一个资助期内，工作集中在平面和相邻Si（001）表面上的稀土硅化物纳米线以及Si（111）表面上的相应纳米结构上。在第二个资助期，重点将转移到各向异性和相邻Si表面上的稀土硅化物纳米线。此外，还将研究过渡金属纳米线等替代材料系统。对于这些新的纳米线系统，生长条件将被优化，特别是获得足够薄的硅化物纳米线与相应的一维电子特性。然后，原子结构和电子性质将被详细研究，也为加盖纳米线。此外，将研究元素纳米线系统，例如Si（111）和Ge（001）上的Au。此外，光学研究，传输实验和理论建模将在该研究小组的合作项目中进行，以获得对纳米线系统的物理特性的全面了解。

This project focuses on the atomic structure and electronic properties of rare earth and transition metal silicide nanowires formed on Si surfaces. The atomic structure is characterized using scanning tunneling microscopy, grazing incidence x-ray diffraction, and low-energy electron diffraction, also with spot-profile analysis and with intensity-voltage analysis. Angle-resolved photoelectron spectroscopy and scanning tunneling spectroscopy are applied for studying the (local) electronic properties. Two strategies for the selforganized nanowire formation are applied, using anisotropic strain of the grown silicides as well as anisotropic substrates. In the first funding period, the work concentrated on rare earth silicide nanowires on the planar and vicinal Si(001) surfaces as well as on corresponding nanostructures on the Si(111) surface. In the second funding period, the focus will shift to rare earth silicide nanowires on anisotropic and vicinal Si surfaces. In addition, alternative material systems such as transition metal nanowires will be studied. For these novel nanowire systems, the growth conditions will be optimized, in particular to obtain sufficiently thin silicide nanowires with corresponding one-dimensional electronic properties. Then the atomic structure and electronic properties will be studied in detail, also for capped nanowires. Moreover, elemental nanowire systems such as Au on Si(111) and Ge(001) will be studied. In addition, optical studies, transport experiments, and theoretical modeling will be performed in cooperating projects in this research group in order to obtain a throughout understanding of the physical properties of the nanowire systems.