Formation and properties of metallic atomic chains and wires

We discuss the current state of a promising area of modern physics, the study of the physical properties of metal nanowires and atomic chains. One-dimensional nanostructures are attractive because of both the promise of their practical applications and the possibility of using them to test various theoretical models and approaches by comparing theoretical results with experimental data. We describe experimental conditions under which metal nanowires form on metal and semiconductor surfaces. We give special attention to theoretical models describing the scenario of nanowire growth on various surfaces. We analyze the main experimentally determined factors that affect the distribution of nanowire lengths. We show that the distribution of nanowire lengths on metal and semiconductor surfaces depends not only on external parameters but also on the formation time. We consider the magnetic properties of finite-length atomic chains located on the surfaces of metal and semiconductor crystals. We demonstrate a correlation among the structural, electronic, and magnetic properties of nanowires. We elucidate the effect that nanowires exert on the electronic properties of the surface on which they form. The nature of edge states is explained. The electron states of nanowire atoms are shown to be sensitive to the nanowire length. We discuss the Rashba effect for metal nanowires on a semiconductor surface and analyze how the exchange energy between atoms and the magnetic anisotropy energy affect the macroscopic characteristics of nanowires, such as their critical temperature and the time of spontaneous magnetization reversal.