QCD Phase Diagram with 2-flavor Lattice Fermion Formulations

TL;DR

This paper introduces a new lattice QCD framework using Karsten-Wilczek fermions with species-dependent imaginary chemical potential, enabling finite temperature and density studies while preserving chiral symmetry.

Contribution

It proposes a novel lattice fermion formulation that simplifies finite-(T,μ) QCD simulations without breaking chiral symmetry.

Findings

Derived the effective potential of the scalar meson field.

Obtained a critical line consistent with expected phase diagram.

Demonstrated applicability through strong-coupling lattice QCD analysis.

Abstract

We propose a new framework for investigating two-flavor lattice QCD with finite temperature and density by applying the Karsten-Wilczek lattice fermion, in which a species-dependent imaginary chemical potential can reduce the number of species to two without losing chiral symmetry. This lattice discretization is useful for study on finite-(T,\mu) QCD since its discrete symmetries are appropriate for the case. To show its applicability, we study strong-coupling lattice QCD with temperature and chemical potential. We derive the effective potential of the scalar meson field and obtain a critical line of the chiral phase transition, which is qualitatively consistent with the phenomenologically expected phase diagram.