[Zurück]

H. Michor, F. Schwarzböck, S. Steiner, C. Gold, E.-W. Scheidt:
"Interplay between Kondo effect, RKKY interaction and crystalline electric field splitting in CeNi₉Ge_4-xGa_x";
Poster: Int. Conference on Strongly Correlated Electron systems, SCES2017, Prague, CZ; 17.07.2017 - 21.07.2017.

Polycrystalline samples of pseudo-ternary solid solutions CeNi₉Ge_4-xGa_x (0≤x≤4) have been investigated by means
of X-ray diffraction, magnetic susceptibility, specific
heat, and electrical resistivity measurements. The new
compound CeNi₉Ga₄ has further been Czochralski grown and studied in single crystalline form. While CeNi₉Ge₄ displays a paramagnetic Kondo ground state with unusual non-Fermi-liquid features, CeNi₉Ga₄ is characterized by rather complex long-range magnetic order with negligible Kondo screening. Well below 1 K a magnetic transition at T_M = 0.6 K is followed by a spin reorientation transition at T^* = 0.17 K. In contrast to
CeNi₉Ge₄, which exhibits a quasi-fourfold degenerated ground state, CeNi₉Ga₄ displays a doublet ground state. The
evolution of the crystalline electric field splitting and of long range magnetic order are discussed and a magnetic
phase diagram for the series CeNi₉Ge_4-xGa_x is constructed on the basis of the Doniach-picture comprising a
magnetically ordered metallic-, a magnetically ordered Kondo-lattice-, and a Fermi-liquid-phase.

Kondo lattice, antiferromagnetic order

http://sces2017.org/components/com_rsform/uploads/58c9421dcf048-T01_Michor_Herwig.pdf