''Elemental analysis - New technique for any element to the few-atom level''

Single-atom counting by Resonance Ionization Spectroscopy (RIS) is a relatively new technology for ultra-trace element analysis. It is being developed by Atom Sciences for a variety of applications. RIS comprises the stepwise excitation, ionization, and counting of atoms of a pre-selected element, generally in a large background of other elements. Because narrowband lasers are used, sufficient optical power enables essentially all of the atoms of the selected element to be ionized, while the interference from other elements remains negligible. Atom Sciences, having been assigned exclusive commercial rights to the RIS patent by the Department of Energy, has combined RIS with ion sputtering for the analysis of solids. The technique has been named Sputter-Initiated Resonance Ionization Spectroscopy (SIRIS)