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Renormalization Group Approach to Spectral Properties of the Two-Channel Anderson Impurity Model

Frithjof B. Anders
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Abstract

The impurity Green function and dynamical susceptibilties for the two-channel Anderson impurity model are calculated. An exact expression for the self-energy of the impurity Green function is derived. The imaginary part of the self-energy scales as $\sqrt{|\w/T_K|}$ for $T\to 0$ serving as a hallmark for non-Fermi behavior. The many-body resonance is pinned to a universal value $1/(2πΔ)$ at $\w=0$. Its shape becomes increasingly more symmetric for the Kondo-regimes of the model. The dynamical susceptibilities are governed by two energy scales $T_K$ and $T_h$ and approach a constant value for $\w\to 0$, whereas relation $χ''(\w)\propto \w$ holds for the single channel model.

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Frithjof B. Anders. 2004-07-07. Renormalization Group Approach to Spectral Properties of the Two-Channel Anderson Impurity Model. https://doi.org/10.1103/physrevb.71.121101

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