PHASE TRANSITION IN THE LINEAR SIGMA MODEL OF THE TWO-COMPONENT MIXING SYSTEM

Abstract

The thermal and quantum phase transitions are studied basing on the Cornwall-Jackiw-Tomboulis (CJT) effective action approach for the relativistic linear sigma model of the two-component mixing system. After obtaining the expression of the thermodynamic potential in Hartree-Fock (HF) approximation, which preserves the Goldstone theorem, the numerical results show that there may be two phase transition scenarios in the system. The first scenario is the thermal phase transition which can only occur in one component. The second scenario is quantum phase transitions which can occur in both two components. In addition, both these two types of phase transitions belong the second order phase transition.