We discuss the chiral and pion-superfluidity phase transitions at finite isospin chemical potential within the framework of Dyson–Schwinger equations. With the help of the quark scalar and pseudo-scalar condensates, which are widely accepted as order parameters of chiral and pion-superfluidity phase transitions respectively, we show that there is a second-order phase transition at isospin chemical potential μ _I ∼ m _π . Thereafter, we investigate the isospin effects on the chiral phase transition and on the critical point as well as the critical end point (CEP). The chiral phase transition line splits into two lines at finite μ _I , and the CEP splits into two CEPs as well.

我们在 Dyson-Schwinger 方程的框架内讨论了有限同位旋化学势下的手性和 pion-超流态相变。借助分别被广泛接受为手性和π-超流态相变的有序参数的夸克标量和伪标量凝聚体，我们表明在同位旋化学势μ _I ∼ m _π处存在二阶相变. 此后，我们研究了同位旋对手性相变和临界点以及临界终点 (CEP) 的影响。手性相变线在有限μ _I处分裂为两条线，CEP 也分裂为两个 CEP。