Electronic structure and the Fermi surface of PuCoGa and NpCoGa

Maehira, Takahiro; Hotta, Takashi; Ueda, Kazuo; Hasegawa, Akira*

By using a relativistic linear augmented-plane-wave method, we clarify energy band structures and Fermi surfaces of recently discovered plutonium-based superconductor PuCoGa. We find several cylindrical sheets of Fermi surfaces with large volume, quite similar to CeMIn (M=Ir and Co) isostructural with PuCoGa, in spite of different -electron numbers between Ce and Pu ions. This similarity is simply understood by a concept of electron-hole conversion in a tight binding model constructed based on the - coupling scheme. Due to the present results, we provide a possible scenario to explain why a transition temperature is so high as 18.5K in PuCoGa.