In the framework of the truncated Dyson-Schwinger equation for the fermion propagator, we investigate the chiral and fermion number susceptibility at finite temperature and chemical potential in quantum electrodynamics in ($2+1$) dimensions (${\mathrm{QED}}_3$). The critical end point in the phase diagram of ${\mathrm{QED}}_3$ is identified, and the behavior of these two susceptibilities around the critical end point is highlighted.

• Received 23 June 2012

DOI:https://doi.org/10.1103/PhysRevD.86.065002