Competing Electronic Configurations for PuTe and New Insight on Plutonium Metal

The electronic structure of plutonium metal and its compounds pose a grand challenge for a fundamental understanding of the Pu-5$f$ electron character. For 30 years the plutonium chalcogenides have been especially challenging, and multiple theoretical scenarios have been proposed to explain their unusual behavior. We present extensive high-resolution photoemission data on a single crystal of PuTe, which has also been proposed as a topological insulator. The new experimental results on this mixed-valent material provide a constraint to the theoretical modeling and new dynamical mean-field theory calculations agree with the experimental results. Comparisons with Pu metal provide new insight in understanding its complex electronic structure.