Pattern of chiral symmetry restoration at finite temperature in a supersymmetric composite model

The structure of chiral symmetry restorations at finite temperature is thoroughly investigated in the supersymmetric Nambu–Jona–Lasinio model with a soft supersymmetry breaking term. It is found that the broken chiral symmetry at vanishing temperature is restored at sufficiently high temperature in two patterns, i.e., the first order and second order phase transition depending on the choice of the coupling constant G and the supersymmetry breaking parameter Δ. The critical curves expressing the phase boundaries in the G−Δ plane are completely determined and the dynamically generated fermion mass is calculated as a function of temperature.