标题： Q状态Potts模型在简单立方晶格上的配分函数零点 显示英文标题

标题： Partition function zeros of the Q-state Potts model on the simple-cubic lattice

摘要： 在简单立方晶格上的$Q$状态 Potts 模型是通过有限晶格上的精确配分函数零点来研究的。 在铁磁相和反铁磁相中，该模型的临界行为是基于复数温度平面上零点分布进行讨论的。 利用低温级数展开估算在无磁场（$H_q=0$）情况下，复数温度平面上与物理临界点共存的复数温度奇点处的特征指数。 我们还研究了非零磁场下 Potts 模型的配分函数零点。 对于$H_q>0$，物理临界点消失，并在复数温度平面上出现 Fisher 边缘奇点。 利用高磁场、低温级数展开计算 Fisher 边缘奇点处的特征指数。 似乎 Fisher 边缘奇点与 Yang-Lee 边缘奇点有关，后者出现在非零磁场（$T>T_c$）情况下的复数磁场平面上。 显示英文摘要

摘要： The $Q$-state Potts model on the simple-cubic lattice is studied using the zeros of the exact partition function on a finite lattice. The critical behavior of the model in the ferromagnetic and antiferromagnetic phases is discussed based on the distribution of the zeros in the complex temperature plane. The characteristic exponents at complex-temperature singularities, which coexist with the physical critical points in the complex temperature plane for no magnetic field ($H_q=0$), are estimated using the low-temperature series expansion. We also study the partition function zeros of the Potts model for nonzero magnetic field. For $H_q>0$ the physical critical points disappear and the Fisher edge singularities appear in the complex temperature plane. The characteristic exponents at the Fisher edge singularities are calculated using the high-field, low-temperature series expansion. It seems that the Fisher edge singularity is related to the Yang-Lee edge singularity which appears in the complex magnetic-field plane for $T>T_c$.