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arXiv · 1706.08443

One- and two-channel Kondo model with logarithmic Van Hove singularity: a numerical renormalization group solution

A. K. Zhuravlev·A. O. Anokhin·V. Yu. Irkhin
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Abstract

Simple scaling consideration and NRG solution of the one- and two-channel Kondo model in the presence of a logarithmic Van Hove singularity at the Fermi level is given. The temperature dependences of local and impurity magnetic susceptibility and impurity entropy are calculated. The low-temperature behavior of the impurity susceptibility and impurity entropy turns out to be non-universal in the Kondo sense and independent of the $s-d$ coupling $J$. The resonant level model solution in the strong coupling regime confirms the NRG results. In the two-channel case the local susceptibility demonstrates a non-Fermi-liquid power-law behavior.

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A. K. Zhuravlev, A. O. Anokhin, V. Yu. Irkhin. 2018-01-03. One- and two-channel Kondo model with logarithmic Van Hove singularity: a numerical renormalization group solution. https://doi.org/10.1016/j.physleta.2017.12.043

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