Comparison between the continuum threshold and the Polyakov loop as deconfinement order parameters

TL;DR

This paper compares the continuum threshold and Polyakov loop as deconfinement order parameters using a nonlocal SU(2) chiral quark model, showing they provide consistent information about deconfinement at finite temperature and chemical potential.

Contribution

It establishes a direct relation between the continuum threshold and the Polyakov loop as deconfinement indicators within a nonlocal SU(2) model, including finite chemical potential effects.

Findings

Both order parameters indicate the same deconfinement transition.

Critical temperatures for deconfinement coincide at zero density.

Evidence for a quarkyonic phase at finite chemical potential.

Abstract

We study the relation between the continuum threshold as function of the temperature $s_0(T)$ within finite energy sum rules and the trace of the Polyakov loop $\Phi$ in the framework of a nonlocal SU(2) chiral quark model, establishing a contact between both deconfinement order parameters at finite temperature $T$ and chemical potential $\mu$. In our analysis, we also include the order parameter for the chiral symmetry restoration, the chiral quark condensate. We found that $s_0$ and $\Phi$ providing us the same information for the deconfinement transition, both for the zero and finite chemical potential cases. At zero density, the critical temperatures for both quantities coincide exactly and, at finite $\mu$ both order parameters provide evidence for the appearance of a quarkyonic phase.