Electronic Correlation Induced Expansion of Compensated Electron and Hole Fermi Pockets in delta-Plutonium

TL;DR

This paper investigates how strong electronic correlations in delta-plutonium cause significant expansion of its Fermi surface pockets and mass renormalization, providing new insights into its complex electronic structure.

Contribution

It presents the first combined study of the Fermi surface and mass renormalizations in delta-Pu using advanced correlated electron theories.

Findings

200% correlation-induced volume expansion of Fermi pockets

Consistent hole pocket placement across correlated theories, differing from DFT

Intermediate mass enhancement observed in the Fermi surface pockets

Abstract

Plutonium is a critically important material as the behavior of its 5f-electrons stands midway between the metallic-like itinerant character of the light actinides and localized atomic-core-like character of the heavy actinides. The delta-phase of plutonium (delta-Pu), while still itinerant, has a large coherent Kondo peak and strong electronic correlations coming from its near-localized character. Using sophisticated Gutwiller wavefunction and dynamical mean-field theory correlated theories, we study for the first time the Fermi surface and associated mass renormalizations of delta-Pu together with calculations of the de Haas-van Alphen (dHvA) frequencies. We find a large (200%) correlation-induced volume expansion in both the hole and electron pockets of the Fermi surface in addition to an intermediate mass enhancement. All of the correlated electron theories predict, approximately, the same hole pocket placement in the Brillouin zone, which is different from that obtained in conventional density-functional band-structure theory, whereas the electron pockets from all theories are in, roughly, the same place.