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arXiv · 0903.1942

Low energy scales of Kondo lattices: mean-field perspective

Sébastien Burdin
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Abstract

A review of the low temperature properties of Kondo lattice systems is presented within the mean-field approximation, focusing on the different characteristic energy scales. The Kondo temperature, T_K, and the Fermi liquid coherence energy, T_0, are analyzed as functions of the electronic filling, the shape of the non-interacting density of states, and the concentration of magnetic moments. These two scales can vanish, corresponding to a breakdown of the Kondo effect when an external magnetic field is applied. The Kondo breakdown can also be reached by adding a superexchange term to the Kondo lattice model, which mimics the intersite magnetic correlations neglected at the mean-field level.

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Sébastien Burdin. 2009-03-11. Low energy scales of Kondo lattices: mean-field perspective. https://doi.org/10.1007/978-90-481-2892-1_18

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