Temperature-independent localization of Ce 4f electrons in cerium monoarsenide

Abstract

In order to reveal the valence state of Ce ions and the occupancy number of Ce 4f electrons versus temperature in cerium monoarsenide (CeAs), we perform an ab initio calculation by using a many-body scheme combing density functional theory (DFT) with dynamical mean field theory (DMFT), taking into account the spin-orbit coupling (SOC) interaction and on-site Coulomb repulsion between Ce 4f electrons. Results demonstrate that Ce 4f j=5/2 and j=7/2 manifolds exhibit the metallic and insulating characters, respectively, irrespective of temperature. Ce 4f-4f correlation, Ce 4f-conduction electrons hybridization, SOC interaction and final state effects yield a complicated spectrum function for CeAs. Coupling of 4f atomic configuration transition, hybridization and temperature does not change the localized Ce 4f regime in CeAs. Finally, momentum-resolved electronic spectrum function is also discussed for comparison with experimental angle-resolved photoemission spectrum (ARPES).