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Role of the d-f Coulomb interaction in intermediate valence and Kondo systems: a numerical renormalization group study

A. K. Zhuravlev·V. Yu. Irkhin·M. I. Katsnelson
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Abstract

Using numerical renormalization group method the temperature dependences of the magnetic susceptibility $χ(T)$ and specific heat $C(T)$ are obtained in the single-impurity Anderson model with inclusion of the $d-f$ Coulomb interaction. It is shown that the exciton effects owing to this interaction can change considerably the dependence $C(T)$ in comparison with the standard Anderson model at not too low temperatures, whereas the dependence $χ(T)$ remains universal. The renormalization of the effective hybridization parameter and $f$-level position, which is connected with the $d-f$ interaction, is calculated, a satisfactory agreement with the Hartree-Fock approximation being derived.

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A. K. Zhuravlev, V. Yu. Irkhin, M. I. Katsnelson. 2005-12-20. Role of the d-f Coulomb interaction in intermediate valence and Kondo systems: a numerical renormalization group study. https://doi.org/10.1140/epjb%2Fe2007-00070-2

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