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Phase diagram of the Kondo necklace: a mean-field renormalization group approach

Tatiana G. Rappoport·M. A. Continentino
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Abstract

In this paper we investigate the magnetic properties of heavy fermions in the antiferromagnetic and dense Kondo phases in the framework of the Kondo necklace model. We use a mean field renormalization group approach to obtain a temperature versus Kondo coupling $(T-J)$ phase diagram for this model in qualitative agreement with Doniach's diagram, proposed on physical grounds. We further analyze the magnetically disordered phase using a two-sites approach. We calculate the correlation functions and the magnetic susceptibility that allow to identify the crossover between the spin-liquid and the local moment regimes, which occurs at a {\em coherence} temperature.

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Tatiana G. Rappoport, M. A. Continentino. 2001-06-21. Phase diagram of the Kondo necklace: a mean-field renormalization group approach. https://doi.org/10.1088/0305-4470%2F34%2F49%2F306

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