The finite volume effect on the QCD phase diagram is investigated via the two-flavor Polyakov-loop-modified Nambu-Jona-Lasinio model in the presence of the chiral chemical potential within the mean-field approximation. Our calculations concentrate on the quark condensate, chiral number density and its derivative, namely, QCD susceptibilities. We find the chiral number density decreases as the system size gets smaller. It is also confirmed that the volume of the strongly interacting matter has an influence on the phase diagram, in particular on the crossover region and the location of a chiral transition line. Therefore, the critical end point (CEP) also shifts with system size. On this basis it follows that study of the finite volume effect as well as the chiral chemical potential dedicated to the chiral phase transition and probing the location of the CEP.

• Received 28 February 2020
• Accepted 12 June 2020

DOI:https://doi.org/10.1103/PhysRevD.102.014014