论文标题
具有异常Z_2对称性的一维iSing模型的相图
Phase diagram of a one-dimensional Ising model with an anomalous Z_2 symmetry
论文作者
论文摘要
可以在对称保护拓扑阶段的边界上实现的异常全局对称性，将新的阶段和相变为凝结物理学。在这项工作中，我们使用密度 - 矩阵重质化组方法研究了具有异常Z2对称性的一维模型。除了具有对称性的铁磁阶段外，我们还发现了SU（2）_1共形场理论所描述的一个无间隙阶段，尽管仅在汉密尔顿人中仅存在离散的Z_2对称性。铁磁相和无间隙相之间的相变是连续的，并且具有与无间隙相的临界缩放相同。我们的数值发现是由对称异常引起的可能阶段的理论约束兼容。
Anomalous global symmetries, which can be realized on the boundary of symmetry-protected topological phases, brings new phases and phase transitions to condensed matter physics. In this work, we study a one dimensional model with an anomalous Z2 symmetry, using the density-matrix renormalization group method. Besides a symmetry-breaking ferromagnetic phase, we find a gapless phase described by the SU(2)_1 conformal field theory, despite the existence of only discrete Z_2 symmetry in the Hamiltonian. The phase transition between the ferromagnetic phase and the gapless phase is continuous and has the same critical scaling as in the gapless phase. Our numerical finding is compatible of theoretical constraints on possible phases resulting from the symmetry anomaly.
