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arXiv · hep-lat/0209156

FLIC-Overlap Fermions and Topology

W. Kamleh·D. J. Kusterer·D. B. Leinweber·A. G. Williams
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Abstract

APE smearing the links in the irrelevant operators of clover fermions (Fat-Link Irrelevant Clover (FLIC) fermions) provides significant improvement in the condition number of the Hermitian-Dirac operator and gives rise to a factor of two savings in computing the overlap operator. This report investigates the effects of using a highly-improved definition of the lattice field-strength tensor F_mu_nu in the fermion action, made possible through the use of APE-smeared fat links in the construction of the irrelevant operators. Spurious double-zero crossings in the spectral flow of the Hermitian-Wilson Dirac operator associated with lattice artifacts at the scale of the lattice spacing are removed with FLIC fermions composed with an O(a^4)-improved lattice field strength tensor. Hence, FLIC-Overlap fermions provide an additional benefit to the overlap formalism: a correct realization of topology in the fermion sector on the lattice.

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W. Kamleh, D. J. Kusterer, D. B. Leinweber, A. G. Williams. 2002-09-25. FLIC-Overlap Fermions and Topology. https://doi.org/10.1016/s0920-5632(03)80473-5

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