Highly Correlated Electronic State in the Ferrimagnetic Quadruple Perovskite CuCu3Fe2Re2O12

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 electronic correlations leads 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.