Electronic structure of an adsorbate in a resonator

We report the controlled modification of the electronic structure on a single Mn adsorbate. This modification was achieved by placing the Mn atom within geometrical arrays of adatoms on Ag(111), and it was observed with local tunnelling spectroscopy. The changes result from the coupling between the Mn s level and surface electronic states of the substrate, which are strongly influenced by the size and geometry of the nanocavity. The dimension and geometry of the adatom array thus provide a degree of control over the induced changes.