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A numerical reinvestigation of the Aoki phase with N_f=2 Wilson fermions at zero temperature

E. -M. Ilgenfritz·W. Kerler·M. Mueller-Preussker·A. Sternbeck·H. Stueben
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Abstract

We report on a numerical reinvestigation of the Aoki phase in lattice QCD with two flavors of Wilson fermions where the parity-flavor symmetry is spontaneously broken. For this purpose an explicitly symmetry-breaking source term $h\barψ i γ_{5} τ^{3}ψ$ was added to the fermion action. The order parameter $<\barψ i γ_{5}τ^{3}ψ>$ was computed with the Hybrid Monte Carlo algorithm at several values of $(β,κ,h)$ on lattices of sizes $4^4$ to $12^4$ and extrapolated to $h=0$. The existence of a parity-flavor breaking phase can be confirmed at $β=4.0$ and 4.3, while we do not find parity-flavor breaking at $β=4.6$ and 5.0.

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E. -M. Ilgenfritz, W. Kerler, M. Mueller-Preussker, A. Sternbeck, H. Stueben. 2004-05-03. A numerical reinvestigation of the Aoki phase with N_f=2 Wilson fermions at zero temperature. https://doi.org/10.1103/physrevd.69.074511

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