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arXiv · cond-mat/9912396

Anderson impurity in a correlated conduction band

W. Hofstetter·R. Bulla·D. Vollhardt
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Abstract

We investigate the physics of a magnetic impurity with spin 1/2 in a correlated metallic host. Describing the band by a Hubbard Hamiltonian, the problem is analyzed using dynamical mean-field-theory in combination with Wilson's nonperturbative numerical renormalization group. We present results for the single-particle density of states and the dynamical spin susceptibility at zero temperature. New spectral features (side peaks) are found which should be observable experimentally. In addition, we find a general enhancement of the Kondo scale due to correlations. Nevertheless, in the metallic phase, the Kondo scale always vanishes exponentially in the limit of small hybridization.

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W. Hofstetter, R. Bulla, D. Vollhardt. 2000-06-30. Anderson impurity in a correlated conduction band. https://doi.org/10.1103/physrevlett.84.4417

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