2007/07/02 by Robert Peters, Thomas Pruschke · 1 citation
Physics and Astronomy · #Advanced Condensed Matter Physics #Physics of Superconductivity and Magnetism #Rare-earth and actinide compounds #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.76.245101
published as Phys. Rev. B 76, 245101 (2007)
arxiv created 2007/07/02 · openalex publication_date 2007/12/03 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
We study magnetic ordering of an extended Kondo-lattice model including an additional on-site Coulomb interaction between the itinerant states. The model is solved in the dynamical mean-field theory using the numerical renormalization group approach of Wilson and coworkers [Phys. Rev. B 21, 1003 (1980); Rev. Mod. Phys. 47, 773 (1975); R. Bulla, et al., arXiv:cond-mat/0701105 (unpublished)] as impurity solver. For a bipartite lattice, we find at half-filling the expected antiferromagnetic phase. Upon doping, this phase is gradually suppressed and hints toward phase separation are observed. For large doping, the model exhibits ferromagnetism, the appearance of which can, at first sight, be explained by the Ruderman-Kittel-Kasuya-Yosida interaction. However, for large values of the Kondo coupling J, significant differences from a simple Ruderman-Kittel-Kasuya-Yosida picture can be found. We, furthermore, observe signs of quantum critical points for antiferromagnetic Kondo coupling between the local spins and band states.