Low energy scales of Kondo lattices: mean-field perspective
نویسنده
چکیده
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, TK , and the Fermi liquid coherence energy, T0, are analyzed as functions of the electronic filling, the shape of the noninteracting 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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