Tracing quasiparticle dynamics and hybridization dynamics in PuCoGa5

TL;DR

This study uses advanced theoretical methods to explore how electronic states and quasiparticle behaviors evolve with temperature in the unconventional superconductor PuCoGa5, revealing Dirac fermions and a temperature-driven crossover in 5f electron states.

Contribution

It provides the first detailed temperature-dependent analysis of quasiparticle and hybridization dynamics in PuCoGa5 using embedded dynamical mean-field theory combined with density functional theory.

Findings

Identification of Dirac fermions in PuCoGa5

Observation of a temperature-driven localized-itinerant crossover of 5f states

Discovery of a characteristic hybridization gap onset at ~290 K

Abstract

PuCoGa5 has attracted significant attention due to its record-breaking superconducting transition temperature Tc=18.5 K among known f-electron superconductors. Here we systematically investigated the evolution of correlated electronic states in the plutonium-based unconventional superconductor PuCoGa5 upon temperature using the embedded dynamical mean-field theory merged with density functional theory. The mixed-valence nature of PuCoGa5 leads to intriguing quasiparticle dynamics and hybridization dynamics. Our findings reveal the presence of Dirac fermions and a temperature-driven localized-itinerant crossover of 5f states. As the temperature decreases, the low-energy quasiparticle resonances develop gradually, while the high-energy quasiparticle resonances exhibit quite different behaviors with an initial increase and subsequent decrease. Furthermore, we identified a characteristic temperature of approximately 290 K for the onset of hybridization gaps, which is much lower than the coherence temperature 580 K for 5f electrons. These results provide valuable insight on the the electronic structures, quasiparticle dynamics, and hybridization processes in 5f correlated electron systems.