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arXiv · 1206.0969

Phase structure for lattice fermions with flavored chemical potential terms

Tatsuhiro Misumi
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Abstract

We discuss the chiral phase diagram in the parameter space of lattice QCD with minimal-doubling fermions, which can be seen as lattice fermions with flavored chemical potential terms. We study strong-coupling lattice QCD with the Karsten-Wilczek formulation, which has one relevant parameter $μ_{3}$ as well as gauge coupling and a mass parameter. We find a nontrivial chiral phase structure with a second-order phase transition between chiral symmetric and broken phases. To capture the whole structure of the phase diagram, we study the related lattice Gross-Neveu model. The result indicates that the chiral phase transition also exists in the weak-coupling region. From these results we speculate on the $μ_{3}$-$g^{2}$ chiral phase diagram in lattice QCD with minimal-doubling fermions, and discuss their application to numerical simulations.

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Tatsuhiro Misumi. 2012-07-28. Phase structure for lattice fermions with flavored chemical potential terms. https://doi.org/10.1007/jhep08(2012)068

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