Combined scanning tunneling microscopy and reflectance anisotropy spectroscopy study of self-organized anisotropic cobalt nanodots on a vicinal Au(111) surface
Résumé
We report on a combined study of two dimensional long-range ordered growth of anisotropic cobalt nanostructures on Au(11,12,12) by means of in-situ scanning tunneling microscopy (STM) and reflectance anisotropy spectroscopy (RAS). The main structure observed in the RA spectra originates from the plasma resonances that occur in the anisotropic Co nanostructures. A simple model allows us to reproduce the general behavior of this structure, in agreement with the Co nanostructure morphologies extracted from the STM images. Moreover, a real-time investigation by RAS during Co deposition at a fixed photon energy allows us to follow the self-organized growth regimes. RAS appears to be a versatile technique which is sensitive to the anisotropic shape of metal nanodots.