Spatial and spectroscopic profiles of the Kondo resonance for magnetic atoms on metal surfaces

Manifestations of the Kondo effect on an atomic length scale on and around magnetic atoms adsorbed on a nonmagnetic metal surface differ depending on which spectroscopic mode the scanning tunneling microscope is operated. In a previous report [T. Kawasaka, H. Kasai, and A. Okiji, Phys. Lett. A 250, 403 (1998)], we suggested the possibility that the Kondo effect can be directly observed as protrusions (peaks) in the spatial distribution of the tunneling current. By comparing the spatial distributions of the conduction electron and localized electron wave function, we show that the protrusions (peaks) observed in the spatial distribution of the tunneling current correspond to the resonances observed in the differential conductance spectra. Furthermore, we investigate the temperature dependence of the spatial distribution of the tunneling current and of the differential conductance to study the electronic properties of various metal-adatom systems. (C) 1999 American Institute of Physics. [S0021-8979(99)06124-1].