Rui Silva scientific activity has been in nuclear condensed matter physics, mainly using ion implantation to modify and form materials – metals and insulating oxides – with novel properties, either localized or extended, and ion beams to characterize and study those and other materials. His main subjects of study are the formation and characterization of nanostructures by ion implantation, with emphasis in intermetallic compounds in metals, and on the electrical and magnetic properties of nanosized metallic structures in oxides, e.g. MgO and TiO2 or ZnO. Combination of ion beam analysis with other structural characterization techniques e.g. XRD and Electron Microscopy, and transport measurements, e.g. electrical conductivity and magnetization measurements M(H) and M(T), yield fundamental information about the relationship of the electronic and spin properties with the structure dimensions and crystalline structure.