1. Orbital selective coupling in CeRh$_3$B$_2$: co-existence of high Curie and high Kondo temperature
- Author
-
Amorese, Andrea, Hansmann, Philipp, Marino, Andrea, Korner, Peter, Willers, Thomas, Walters, Andrew, Zhou, Kejin, Kummer, Kurt, Brooks, Nicholas B., Lin, Hong-Ji, Chen, Cien-Te, Lejay, Pascal, Haverkort, Maurits W., Tjeng, Liu Hao, and Severing, Andrea
- Subjects
Condensed Matter - Strongly Correlated Electrons - Abstract
We investigated the electronic structure of the enigmatic CeRh$_3$B$_2$ using resonant inelastic scattering and x-ray absorption spectroscopy in combination with $ab$ $initio$ density functional calculations. We find that the Rh 4$d$ states are irrelevant for the high-temperature ferromagnetism and the Kondo effect. We also find that the Ce 4$f$ crystal-field strength is too small to explain the strong reduction of the Ce magnetic moment. The data reveal instead the presence of two different active Ce 4$f$ orbitals, with each coupling selectively to different bands in CeRh$_3$B$_2$. The inter-site hybridization of the |J=5/2,Jz=+/-1/2> crystal-field state and Ce 5$d$ band combined with the intra-site Ce 4$f$-5$d$ exchange creates the strong ferromagnetism, while hybridization between the |J=5/2,Jz=+/-5/2> and the B $sp$ in the $ab$-plane contributes to the Kondo interaction which causes the moment reduction. This orbital selective coupling explains the unique and seemingly contradictory properties of CeRh$_3$B$_2$., Comment: 15 pages, 14 figures
- Published
- 2022
- Full Text
- View/download PDF