Evolution of the Kondo Resonance for Screened Atoms on Metals and Thin Insulators

We study the magnetic anisotropy and the Kondo screening of the spin of Co atoms deposited on Cu$_{2}$N using scanning tunneling microscopy and spectroscopy. We find that for Co atoms placed on Cu$_{2}$N islands the Kondo screening is weaker when the atom is very close to the edge and at the same time has significant changes in the magnetic anisotropy. Furthermore we observe that Co atoms that are placed on the Cu surface but near the Cu$_{2}$N islands still show anisotropy and an unusually small Kondo temperature. At larger distances from the Cu$_{2}$N islands the usual large Kondo temperature recovers. We examine possible causes for these dramatic changes in the Kondo screening and magnetic anisotropy, including a possible extension of the electronic properties of the Cu$_{2}$N islands compared to the topographic influence.