PuCoGa5 and related materials

Temperature dependencies of the nuclear spin-relaxation rate and specific heat of PuCoGa5 and isostructural PuRhGa5 are consistent with their superconductivity being unconventional. A simple model of hybridization between localized f-electrons and itinerant conduction-band electrons gives a framework for interpreting basic similarities and differences between these Pu-based superconductors and their Ce-based analogs. This model also provides a rationale for the correlation between Tc and a characteristic spin-energy scale in these materials.