Mamiyev Zamin, Fink Christa, Holtgrewe Kris, Pfnür Herbert, Sanna Simone
Institut für Festkörperphysik, Leibniz Universität Hannover, Appelstraße 2, 30167 Hannover, Germany.
Laboratorium für Nano- und Quantenengineering (LNQE), Leibniz Universität Hannover, Schneiderberg 39, 30167 Hannover, Germany.
Phys Rev Lett. 2021 Mar 12;126(10):106101. doi: 10.1103/PhysRevLett.126.106101.
One-dimensional wires are known to be inherently unstable at finite temperature. Here, we show that long-range order of atomic Au double chains adsorbed on a Si(553) surface is not only stabilized by interaction with the substrate, but spontaneous self-healing of structural defects is actually enforced by the adsorption of atomic species such as Au or H. This is true even for random adsorbate distribution. Combining atomistic models within density functional theory with low energy electron diffraction and high-resolution electron energy loss spectroscopy, we demonstrate that this apparently counterintuitive behavior is mainly caused by adsorption-induced band filling of modified surface bands, i.e., by the strong electronic correlation throughout the whole terrace. Although adsorption preferably occurs at the step edge, it enhances the dimerization and the stiffness of the Au dimers. Thus, the intertwinement of quasi-1D properties with delocalized 2D effects enforces the atomic wire order.
一维金属丝在有限温度下本质上是不稳定的。在此，我们表明吸附在Si(553)表面的原子金双链的长程有序不仅通过与衬底的相互作用得以稳定，而且结构缺陷的自发自我修复实际上是由金或氢等原子物种的吸附所促成的。即使对于随机的吸附质分布也是如此。我们将密度泛函理论中的原子模型与低能电子衍射和高分辨率电子能量损失谱相结合，证明这种明显违反直觉的行为主要是由吸附诱导的修饰表面能带的能带填充引起的，即由整个平台上的强电子相关性引起的。尽管吸附优选发生在台阶边缘，但它增强了金二聚体的二聚化和刚度。因此，准一维性质与离域二维效应的交织强化了原子线序。
