Kinks in strongly correlated electron systems

Full text: Recent dynamical mean field calculations have shown that so-called Kinks emerge in the real part of the self energy ReΣ(ω) of strongly correlated metals close to the Fermi level. This gives rise to a similar behaviour in the quasi-particle dispersion relation Ek and also in the electronic specific heat CV, which was confirmed experimentally for various transition metal compounds such as LiV2O4 or high temperature superconductors. Since f-electron systems are even more strongly correlated than d-electron systems we apply the dynamical mean field approach to the periodic Anderson model and use Wilson's numerical renormalization group method as an impurity solver to study this aspect of the self-energy at low frequencies with high accuracy. (author)