We develop, clarify and test various aspects of cluster methods dynamical mean field methods using a soluble toy model as a benchmark. We find that the Cellular Dynamical Mean Field Theory (C-DMFT) converges very rapidly and compare its convergence properties with those of the Dynamical Cluster Approximation (DCA). We propose and test improved estimators for the lattice self energy within C-DMFT.
@article{arxiv.cond-mat/0107108,
title = {A note on cluster methods for strongly correlated electron systems},
author = {Giulio Biroli and Gabriel Kotliar},
journal= {arXiv preprint arXiv:cond-mat/0107108},
year = {2009}
}