2008/04/30 by E. M. Brüning, C. Krellner, M. Baenitz +4 · 1 citation
Chemistry · Materials Science · Physics and Astronomy · #Inorganic Chemistry and Materials #Iron-based superconductors research #Rare-earth and actinide compounds #cond-mat.mtrl-sci #cond-mat.str-el
paper · pdf · doi:10.1103/physrevlett.101.117206
published as Phys. Rev. Lett. 101, 117206 (2008) · 5 pages, 4 figures
openalex publication_date 2008/09/12 · arxiv created 2008/09/19 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The ground state properties of CeFePO, a homologue of the new high temperature superconductors RFePnO1-xFx, were studied by means of susceptibility, specific heat, resistivity, and NMR measurements on polycrystals. All the results demonstrate that this compound is a magnetically nonordered heavy fermion metal with a Kondo temperature TK approximately 10 K, a Sommerfeld coefficient gamma=700 mJ/mol K2, and a mass enhancement factor of the order of 50. Analysis of the susceptibility data and of the spin relaxation time indicates that the strong electronic correlation effects originate from the Ce-4f electrons rather than from Fe-3d electrons. An enhanced Sommerfeld-Wilson ratio R=5.5 as well as a Korringa product S0/T1TK2 approximately 0.065 well below 1 indicate the presence of ferromagnetic correlations. Therefore, CeFePO appears to be on the nonmagnetic side of a ferromagnetic instability.