Probing deconfinement in the Polyakov-loop extended Nambu-Jona-Lasinio model at imaginary chemical potential

TL;DR

This paper investigates the deconfinement transition in the PNJL model at imaginary chemical potential, revealing how the model's confinement features influence the chiral condensate and introducing a dual parameter to characterize deconfinement.

Contribution

It introduces a dual parameter for deconfinement based on the condensate's dependence on imaginary chemical potential and explores how tuning the coupling affects the critical endpoint.

Findings

The chiral condensate shows characteristic dependence on imaginary chemical potential.

A dual parameter effectively characterizes the deconfinement transition.

The critical endpoint's location can be tuned via the four-fermion coupling.

Abstract

The phase structure of Polyakov-loop extended Nambu-Jona-Lasinio (PNJL) model is explored at imaginary chemical potential, with particular emphasis on the deconfinement transition. We point out that the statistical confinement nature of the model naturally leads to characteristic dependence of the chiral condensate $<\bar{q}q>$ on $\theta=\mu_I/T$. We introduce a dual parameter for the deconfinement transition by making use of this dependence. By changing a four-fermion coupling constant, we tune the location of the critical endpoint of the deconfinement transition.