On the Sign Problem in the Hirsch-Fye Algorithm for Impurity Problems
Strongly Correlated Electrons
2007-05-23 v2
Abstract
We show that there is no fermion sign problem in the Hirsch and Fye algorithm for the single-impurity Anderson model. Beyond the particle-hole symmetric case for which a simple proof exists, this has been known only empirically. Here we prove the nonexistence of a sign problem for the general case by showing that each spin trace for a given Ising configuration is separately positive. We further use this insight to analyze under what conditions orbitally degenerate Anderson models or the two-impurity Anderson model develop a sign.
Cite
@article{arxiv.cond-mat/0412771,
title = {On the Sign Problem in the Hirsch-Fye Algorithm for Impurity Problems},
author = {Jaebeom Yoo and Shailesh Chandrasekharan and Ribhu K. Kaul and Denis Ullmo and Harold U. Baranger},
journal= {arXiv preprint arXiv:cond-mat/0412771},
year = {2007}
}
Comments
2 pages, no figure; published version