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arXiv · 1504.07216

Crystal fields and Kondo effect: new results for the magnetic susceptibility

Hans-Ulrich Desgranges
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Abstract

The thermodynamic Bethe ansatz equations for the Coqblin-Schrieffer model have been solved for the first time to obtain the magnetic susceptibility in the presence of crystal fields for non-zero temperatures. For the case of N = 4 effective ionic states an analytic expression for the limiting values of the pseudo-energies has been found facilitating the numerical solution for various crystal and magnetic field configurations. The single-impurity model applies to a wide range of dense Kondo systems and has been used before to explain apparent non-Fermi-liquid behavior. The flattening off of the susceptibility curves at a substantially higher temperature than the specific heat is shown to be a general feature of the Coqblin-Schrieffer thermodynamics.

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Hans-Ulrich Desgranges. 2015-06-06. Crystal fields and Kondo effect: new results for the magnetic susceptibility. https://doi.org/10.1016/j.physb.2015.05.033

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