Inhomogeneous pion condensate in (1+1)-dimensional massive Nambu--Jona-Lasinio model

The ground state structure of four-fermionic $(1+1)$--dimensional Nambu--Jona-Lasinio model is investigated as a function of the external parameters (chemical potentials). In their presence the model demonstrates the features of dense quark matter in real physical situations. The thermodynamic potential of the model is calculated in the presence of nonzero baryonic $\mu$ and isotopical $\mu_I$ chemical potentials in the limit of large number of colors($N_c\to\infty$). The possibility of the formation of spatially inhomogeneous pion condensate in both massive and massless cases is considered. Detailed analysis of phase structure of the studied model is conducted.