Can competition between crystal field and Kondo effect cause non-Fermi liquid like behavior?
Loading...
Date
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Description
The recently reported unusual behavior of the static and dynamical magnetic susceptibility as well as the specific heat in Ce$_{1-x}$La$_{x}$Ni$_{9}$Ge$_4$ has raised the question of a possible non-Fermi liquid ground state in this material. We argue that for a consistent physical picture the crystal field splitting of two low lying magnetic doublets of the Ce $4f$-shell must be taken into account. Furthermore, we show that for a splitting of the order of the low temperature scale $T^*$ of the system a crossover behavior between an SU(4) and an SU(2) Kondo effect is found. The screening of the two doublets occurs on different temperature scales leading to a different behavior of the magnetic susceptibility and the specific heat at low temperatures. The experimentally accessible temperature regime down to 50mK still lies in the extended crossover regime into a strong coupling Fermi-liquid fixed point.
4 pages, 4 figures, revtex4
4 pages, 4 figures, revtex4