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Heavy-fermion and spin-liquid behavior in a Kondo lattice with magnetic frustration

S. Burdin·D. R. Grempel·A. Georges
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Abstract

We study the competition between the Kondo effect and frustrating exchange interactions in a Kondo-lattice model within a large-${\cal N}$ dynamical mean-field theory. We find a T=0 phase transition between a heavy Fermi-liquid and a spin-liquid for a critical value of the exchange $J_c = T_{K}^0$, the single-impurity Kondo temperature. Close to the critical point, the Fermi liquid coherence scale $T^\star$ is strongly reduced and the effective mass strongly enhanced. The regime $T>T^\star$ is characterized by spin-liquid magnetic correlations and non-Fermi-liquid properties. It is suggested that magnetic frustration is a general mechanism which is essential to explain the large effective mass of some metallic compounds such as LiV$_2$O$_4$.

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S. Burdin, D. R. Grempel, A. Georges. 2002-02-07. Heavy-fermion and spin-liquid behavior in a Kondo lattice with magnetic frustration. https://doi.org/10.1103/physrevb.66.045111

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