Highly correlated electronic state in a ferrimagnetic quadruple perovskite CuCu$_3$Fe$_2$Re$_2$O$_{12}$

TL;DR

This study investigates the strongly correlated electronic state in the ferrimagnetic quadruple perovskite CuCu$_3$Fe$_2$Re$_2$O$_{12}$ using advanced first-principles methods, revealing the importance of many-body effects for its electronic and magnetic properties.

Contribution

It demonstrates the significance of many-body effects in accurately describing the electronic structure of CuCu$_3$Fe$_2$Re$_2$O$_{12}$, showing differences between DFT+U and DFT+DMFT results.

Findings

DFT+U predicts half-metallic ferrimagnetism.

DFT+DMFT indicates a metallic state with strong correlations.

Results align better with experimental data when using DFT+DMFT.

Abstract

Recently synthesized quadruple perovskite CuCu$_3$Fe$_2$Re$_2$O$_{12}$ possesses strong ferromagnetism and unusual electron properties, including enhanced electronic specific heat. Application of the first principles electronic structure approaches unambiguously shows importance of the many-body effects in this compound. While CuCu$_3$Fe$_2$Re$_2$O$_{12}$ is half-metallic ferrimagnet in the DFT+U method, in the density functional theory (DFT) combined with the dynamical mean-field theory (DMFT) it appears to be a metal. Strong correlations lead to a renormalization of electronic spectrum and formation of incoherent states close to the Fermi level. Electronic specific heat and magnetic properties obtained in the DFT+DMFT approach are in better agreement with available experimental data than derived by other band structure techniques.