Two-particle-correlations in a functional renormalization group scheme using a dynamical mean-field theory approach
Abstract
We apply a recently introduced hybridization-flow functional renormalization group scheme for Anderson-like impurity models as an impurity solver in a dynamical mean-field theory (DMFT) approach to lattice Hubbard models. We present how this scheme is capable of reproducing metallic and insulating solutions of the lattice model. Our setup also offers a numerically rather inexpensive method to calculate two-particle correlation functions. For the paramagnetic Hubbard-model on the Bethe lattice in infinite dimensions we calculate the local two-particle-vertex for the metallic and the insulating phase. Then we go to a two-site cluster-DMFT-scheme for the two-dimensional Hubbard-model that includes short-range antiferromagnetic fluctuations and obtain the local and non-local two-particle-vertex-functions. We discuss the rich frequency structures of these vertices and compare with the vertex in the single-site solution.
Cite
@article{arxiv.1307.1298,
title = {Two-particle-correlations in a functional renormalization group scheme using a dynamical mean-field theory approach},
author = {Michael Kinza and Carsten Honerkamp},
journal= {arXiv preprint arXiv:1307.1298},
year = {2013}
}
Comments
22 pages, 15 figures