A Numerical Renormalization Group approach to Green's Functions for Quantum Impurity Models
Strongly Correlated Electrons
2009-11-11 v1
Abstract
We present a novel technique for the calculation of dynamical correlation functions of quantum impurity systems in equilibrium with Wilson's numerical renormalization group. Our formulation is based on a complete basis set of the Wilson chain. In contrast to all previous methods, it does not suffer from overcounting of excitation. By construction, it always fulfills sum rules for spectral functions. Furthermore, it accurately reproduces local thermodynamic expectation values, such as occupancy and magnetization, obtained directly from the numerical renormalization group calculations.
Cite
@article{arxiv.cond-mat/0607494,
title = {A Numerical Renormalization Group approach to Green's Functions for Quantum Impurity Models},
author = {Robert Peters and Thomas Pruschke and Frithjof B. Anders},
journal= {arXiv preprint arXiv:cond-mat/0607494},
year = {2009}
}
Comments
13 pages, 7 figure