First-principles interpretation of scanning tunneling microscopy applied to transition-metal surfaces: Buried CuIr/Cu(001) surface alloys

Abstract

For the example of scanning tunneling microscopy (STM) experiments, carried out for Ir impurities and chains buried in the sub-surface layer of Cu(001), we represent the present status of analyzing STM experiments of transition-metal surfaces using first-principles calculations based on the density functional theory to describe the electronic structure of the sample, in combination with the model of Tersoff and Hamann to evaluate the tunneling current between tip and sample. We show that transition-metal defect structures below the Cu(001) surface can be detected by STM and the detection should not be restricted to Ir defects nor to the sub-surface layer.