One-atom-layer compounds on silicon and germanium

Two-dimensional (2D) compounds having one-atomic-layer thickness represent a novel class of low-dimensional materials with potentially advanced properties. In the present progress review, we overview the recent results on the 2D compounds of metallic adsorbates on Si(111) and Ge(111) surfaces. The main attention is focused on their contribution to the very modern subjects of the surface science, namely surface Rashba effect and surface superconductivity. The possible prospects of studying 2D compounds are briefly discussed.