https://doi.org/10.1140/epjb/e2004-00256-0
Renormalized parameters for impurity models
1
Department of Mathematics, Imperial College, London SW7 2BZ, UK
2
Department of Material Science, Osaka City University, Sumiyoshi-ku, Osaka 558-8585, Japan
Corresponding author: a d.meyer@ic.ac.uk
Received:
6
May
2004
Revised:
2
July
2004
Published online:
12
August
2004
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 
, an effective hybridization 
, and a quasiparticle
interaction 
. 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.
PACS: 75.20.Hr – Local moment in compounds and alloys; Kondo effect, valence fluctuations, heavy fermions / 71.10.-w – Theories and models of many-electron systems / 71.27.+a – Strongly correlated electron systems; heavy fermions
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2004
