Pressure Effect on the Superconductivity of AnTGa5 Systems and Americium Metal (An=Np, Pu, Am - T=Co, Rh, Ir)

Abstract

AbstractWe report pressure studies on the magnetic and superconducting properties of PuTGa5 (T=Co, Rh) and Americium metal down to 0.4K. Recent discovery of superconductivity in the Plutonium based compounds PuTGa5 (T=Co, Rh) has shed a new light on the study of Actinides compounds. The fact that these systems present lots of similarities with the CeTIn5 (T=Co, Rh, Ir) must not hide some fascinating features of these materials: they display superconducting characteristics one order of magnitude higher than their Cerium counterparts or all 5f Superconducting Heavy. Moreover they present at ambient pressure a Non Fermi Liquid described by a T4/3 law which seems to maintain up to the highest pressure achieved (∼20 GPa) for the 2 Plutonium superconductors. Finally we report superconducting pressure diagram of americium metal under pressure up to 27 GPa and down to 0.4K. The complex superconducting diagram Tc(p) related to the several phases transition led us to examine the localization delocalization aspect of the 5f electrons in this metal through the Mott transition.