Self-consistent spin-fluctuation spectrum and correlated electronic structure of actinides

TL;DR

This paper develops a self-consistent theoretical approach combining ab-initio band structure and spin-fluctuation effects to analyze the electronic properties of actinides, revealing the coexistence of itinerant and incoherent features.

Contribution

It introduces an intermediate Coulomb-U coupling model with self-consistent GW corrections tailored for actinides, providing detailed insights into their spin-fluctuation spectra and electronic structure.

Findings

Spin fluctuations around 0.5 eV significantly influence electronic properties.

The model accurately reproduces photoemission spectra and quantum oscillation data.

Actinides are well described by an intermediate Coulomb interaction regime.

Abstract

We present an overview of various theoretical methods with detailed emphasis on an intermediate Coulomb-U coupling model. This model is based on material-specific ab-initio band structure from which correlation effects are computed via self-consistent GW-based self-energy corrections arising from spin-fluctuations. We apply this approach to four isostructural intermetallic actinides PuCoIn5, PuCoGa5, PuRhGa5 belonging to the Pu-115 family, and UCoGa5, a member of the U-115 family. The 115 families share the property of spin-orbit split density of states enabling substantial spin fluctuations around 0.5 eV, whose feedback effect on the electronic structure create mass renormalization and electronic `hot spots`, i.e., regions of large spectral weight. A detailed comparison is provided for the angle-resolved and angle-integrated photoemission spectra and de Haas-van Alphen experimental data as available. The results suggest that this class of actinides is adequately described by the intermediate Coulomb interaction regime, where both itinerant and incoherent features coexist in the electronic structure.