Clusters on semiconductor surfaces

Recent theoretical analysis and experimental investigations indicate that the physics of clusters deposited on semiconductor surfaces such as Silicon may be a promising future avenue for nanostructure science. Clusters of small number (5 - 10) of atoms in free space have also been shown to have interesting energy structures as well as magnetic and electrical moments. We report on the formation of Mn islands on Si(111) surfaces and their optical scattering response. We show that Mn islands of diameter 15 to 30nm exhibit paramagnetism at low temperatures, while thick films of Mn do not. In addition, our experiments verify previous theoretical suggestions that polarized optical scattering can be used to detect magnetism in small clusters. We will discuss some of these along with possible future applications of cluster physics.