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Renormalized Parameters for Impurity Models

A. C. Hewson·A. Oguri·D. Meyer
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Abstract

We show that the low energy behaviour of quite diverse impurity systems can be described by a single renormalized Anderson model, with three parameters, an effective level $\tildeε_d$, an effective hybridization $\tilde V$, and a quasiparticle interaction $\tilde U$. The renormalized parameters are calculated as a function of the bare parameters for a number of impurity models, including those with coupling to phonons and a Falikov-Kimball interaction term. In the model with a coupling to phonons we determine where the interaction of the quasiparticles changes sign as a function of the electron-phonon coupling. In the model with a Falikov-Kimball interaction we show that to a good approximation the low energy behaviour corresponds to that of a bare Anderson model with a shifted impurity level.

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A. C. Hewson, A. Oguri, D. Meyer. 2004-05-11. Renormalized Parameters for Impurity Models. https://doi.org/10.1140/epjb%2Fe2004-00256-0

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