The action of the overlap-Dirac operator on a vector is typically implemented indirectly through a multi-shift conjugate gradient solver. The compute-time required depends upon the condition number, κ, of the matrix that is used as the overlap kernel. While the Wilson action is typically used as the overlap kernel, the FLIC (Fat Link Irrelevant Clover) action has an improved condition number and provides up to a factor of two speedup in evaluating the overlap action. We summarize recent progress on the use of FLIC overlap fermions.
@article{arxiv.hep-lat/0209155,
title = {FLIC Overlap Fermions},
author = {W. Kamleh and D. B. Leinweber and A. G. Williams and J. B. Zhang},
journal= {arXiv preprint arXiv:hep-lat/0209155},
year = {2010}
}