Pion Condensation at Finite Temperature and Density; the Role of Charge Neutrality

We study the phase structure of the two-flavor Nambu-Jona-Lasinio model in the presence of baryon and isospin chemical potential at zero and finite temperature. Any finite value of the chemical potentials restores chiral symmetry, while there is a charged pion condensate for small chemical potentials which depend on temperature. We also examine the effects of imposing charge neutrality and weak equilibrium on the phase structure of the model. In this case, there is window of baryon chemical potential and temperature where the charged pions condense