QCD phase diagram with the improved Polyakov loop effective potential

We report our recent progress on the QCD phase structure.We explore the properties of quark–gluon matter in the improved Polyakov–Nambu–Jona–Lasinio(PNJL)model by introducing a chemical potential-dependent Polyakov loop potential.This treatment effectively reflects the quantum backreaction of matter sector to glue sector at nonzero chemical potential.Compared with the original PNJL model,a superiority of the improved PNJL model is that it can effectively describe the confinement–deconfinement transition at low temperature and high density.And the QCD phase diagram will be modified to a certain degree if the strength of the quantum backreaction of matter sector to glue sector is strong.One evident variation is that the region of quarkyonic phase will be greatly reduced in the improved PNJL model.This means that the modification to the Polyakov loop potential with the chemical potential dependence is possibly a significant improvement in exploring the full QCD phase structure.