Structure of the indium-rich InSb(001) surface

作     者：G. Goryl D. Toton N. Tomaszewska J. S. Prauzner-Bechcicki L. Walczak A. Tejeda A. Taleb-Ibrahimi L. Kantorovich E. G. Michel J. J. Kolodziej 

作者机构：Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University Kraków Poland Department of Physics King’s College London Gower Street London United Kingdom Depto. de Fisica de la Materia Condensada Universidad Autónoma de Madrid Madrid Spain Synchrothron SOLEIL Gif-sur-Yvette France 

出 版 物：《Physical Review B》 (物理学评论B辑：凝聚态物质与材料物理学)

年 卷 期：2010年第82卷第16期

页      面：165311-165311页

核心收录：

学科分类：07[理学] 0702[理学-物理学] 

基　　金：Engineering and Physical Sciences Research Council  EPSRC  (EP/F067496/1) 

摘      要：The indium-rich InSb(001) surface, that shows the c(8×2) reconstruction at room temperature and a partially disordered phase at 77 K (the low temperature or LT phase), is studied experimentally by means of scanning probe microscopies, low-energy electron diffraction, and angle-resolved photoelectron spectroscopy (ARPES), as well as theoretically, using the density-functional theory (DFT). The experimental studies are done both at room temperature and at cryogenic temperatures. No metallic surface bands are found using ARPES, consequently the idea of charge-density waves as a possible explanation of the LT phase suggested previously by Goryl et al. [Surf. Sci. 601, 3605 (2007)] is discarded. On the other hand it is shown that an essential core of the surface structure is described by the so-called ζ model which has the c(8×2) symmetry. However, on top of this basic structure there are additional not fully occupied indium-atom rows. Vacancies/atoms in these rows rapidly fluctuate at room temperature while, upon cooling down, they stabilize to form a sublattice also of c(8×2) symmetry. Furthermore, this sublattice has shifted mirror symmetry axes (relating to those of the underlying ζ lattice) therefore the surface symmetry is lowered from c2mm to p2 and structural domains are formed. This occurs with no significant core ζ lattice distortions but dense domain borders lead to significant disorder in the top atomic layer. DFT calculations confirm that the postulated ζ-like structure with additional 50% occupied indium-atom rows is stable on the InSb (001) surface. Calculated, in the Tersoff-Hammann approximation, scanning tunneling microscopy (STM) images of the relaxed surface structure agree well with experimental STM images.