Correlation effects in electronic structure of PuCoGa5

TL;DR

This paper presents the first realistic electronic structure calculations of PuCoGa5 using dynamical mean field theory, revealing how local Coulomb interactions influence its electronic properties and potentially promote superconductivity.

Contribution

It introduces a dynamical mean field theory approach to PuCoGa5, showing the importance of dynamical correlations over static ones in understanding its electronic structure.

Findings

Dynamical correlations create a narrow peak near the Fermi energy.

Both Pu and Co significantly contribute to the density of states at the Fermi level.

A Van Hove singularity near the Fermi energy may enhance magnetic susceptibility and support d-wave superconductivity.

Abstract

We report on results of the first realistic electronic structure calculations of the Pu-based PuCoGa5 superconductor based on the dynamical mean field theory. We find that dynamical correlations due to the local Coulomb interaction between Pu f-electrons lead to substantial modification of the electronic structure with a narrow peak being formed in vicinity of the Fermi energy, in agreement with the experimental photoemission spectra, and in contrast with the recent calculations within the LDA+U method, where only static electronic correlations have been included. Both Pu and Co contribute in equal footing to the narrow peak on the density of states at the Fermi level, the Co partial density of states being prominently affected by electronic correlations on the Pu sites. The k-resolved spectral density is calculated and the theoretical spectral function resolved extended Van Hove singularity near the Fermi energy. This singularity may lead to enchancement of the magnetic susceptebility and favour d-wave superconductivity.