We extend the Polyakov-loop extended Nambu-Jona-Lasinio (PNJL) model by introducing an effective four-quark vertex depending on Polyakov loop. The effective vertex generates entanglement interactions between Polyakov loop and chiral condensate. The new model is consistent with lattice QCD data at imaginary quark-number chemical potential and real and imaginary isospin chemical potentials, particularly on strong correlation between the chiral and deconfinement transitions and also on the quark-mass dependence of the order of the Roberge-Weiss endpoint predicted by lattice QCD very lately. We investigate an influence of the entanglement interactions on a location of the tricritical point at real isospin chemical potential and a location of the critical endpoint at real quark-number chemical potential.
@article{arxiv.1006.3648,
title = {Entanglement between deconfinement transition and chiral symmetry restoration},
author = {Yuji Sakai and Takahiro Sasaki and Hiroaki Kouno and Masanobu Yahiro},
journal= {arXiv preprint arXiv:1006.3648},
year = {2014}
}