Fermi Surface Topology and Correlation Effects in the Electronic Structure of Plutonium

Due to its position at the boundary between the light and heavy actinides, the electronic structure of Pu has exotic physical properties that are complex and challenging to model. The difficulties in performing accurate theoretical calculations for this element stem from the liminal characteristics of Pu-5f orbital electrons and understanding the role of the fluctuating magnetism in the electronic structure. Two methods for treating the magnetic behavior in Pu are currently debated. One is the “disordered local moment” model described by density functional theory (DFT) and the other is the “valence fluctuation” model as captured by dynamical mean-field theory (DMFT). Focusing on the
δ-phase of elemental Pu, we perform a careful comparison of Fermi surface topology calculations using DFT and DFT+U. The de Haas-van Alphen (dHvA) frequencies at the Fermi surface and band masses are calculated in both magnetic and nonmagnetic states. We also analyze the effective mass enhancement due to 5f-electron correlation effects with DMFT. The comparison study will be helpful for future experiments to validate theoretical modeling.