Phase diagram of the Kondo necklace: a mean-field renormalization group approach
arXiv:cond-mat/0106419 · doi:10.1088/0305-4470/34/49/306
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 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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