Growth and structure of Ag on bilayer Co nanoislands on Cu(111)

We have studied the growth of Ag on bilayer high Co nanoislands on Cu(111) using Scanning Tunneling Microscopy. Noble metal capping of magnetic nanostructures is known to influence the magnetism and knowledge of the growth is therefore important. We find that Ag preferentially nucleates on the Co nanoislands initially leaving the free Cu sites clean. Furthermore we observe, that those Co islands which are capped with Ag are almost completely capped thus making a perfect multilayered system of Ag/Co/Cu(111). We observe a (9$\times$9) reconstruction of the Ag overlayer on Co/Cu(111).