A first principle calculation on electronic properties of plutonium mononitride: Insights from dynamical mean field theory

We perform a first principles calculation on electronic properties of plutonium mononitride (PuN) using a many-body method merging local density approximation (LDA) with dynamical mean field theory (the so called LDA + DMFT scheme), taking into account the on-site Coulomb interaction between Pu 5f states and spin-orbit coupling due to high atomic number of plutonium element. We find that PuN is a mixed-valentnf = 4.823 moderately correlated system and a triplet of quasiparticle peaks below the Fermi level corresponding to multiplet of many-body quasiparticle peaks are due to valence fluctuations and the Pu atomic multiplet structure, which is agreement with the photo-electron spectroscopy observation. The calculation result reveals that the low energy scattering rate from the imaginary part of the self energy is very large, indicating that PuN is a bad metal, which is also in agreement with the density of states (DOS) analysis and other theoretical calculation. In order to compare with experimental angle-resolved photoemission spectrum (ARPES), we also calculate momentum-resolved electronic spectrum function, and analyze electronic excitation across the Fermi level.