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Renormalized perturbation calculations for the single impurity Anderson model

A. C. Hewson
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Abstract

We illustrate the renormalized perturbation expansion method by applying it to a single impurity Anderson model. Previously, we have shown that this approach gives the {\it exact} leading order results for the specific heat, spin and charge susceptibilities and leading order temperature dependence of the resistivity for this model in the Fermi-liquid regime, when carried out to second order in the renormalized interaction $\tilde U$. Here we consider the effects of higher order quasi-particle scattering and calculate the third order contributions to the $H^3$ term in the impurity magnetization for the symmetric model in a weak magnetic field $H$. The result is asymptotically exact in the weak coupling regime, and is very close to the exact Bethe ansatz result in the Kondo regime. We also calculate the quasi-particle density of states in a magnetic field, which is of interest in relation to recent experimental work on quantum dots.

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A. C. Hewson. 2001-06-28. Renormalized perturbation calculations for the single impurity Anderson model. https://doi.org/10.1088/0953-8984%2F13%2F44%2F314

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