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Kondo resonance for orbitally degenerate systems

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

Formation of the Kondo state in general two-band Anderson model has been investigated within the numerical renormalization group (NRG) calculations. The Abrikosov-Suhl resonance is essentially asymmetric for the model with one electron per impurity (quarter filling case) in contrast with the one-band case. An external magnetic (pseudo-magnetic) field breaking spin (orbital) degeneracy leads to asymmetric splitting and essential broadening of the many-body resonance. Unlike the standard Anderson model, the ``spin up'' Kondo peak is pinned against the Fermi level, but not suppressed by magnetic field.

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A. K. Zhuravlev, V. Yu. Irkhin, M. I. Katsnelson, A. I. Lichtenstein. 2004-11-12. Kondo resonance for orbitally degenerate systems. https://doi.org/10.1103/physrevlett.93.236403

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