论文标题
使用离散模型模拟连续对称模型
Simulating continuous symmetry models with discrete ones
论文作者
论文摘要
尤其是在一个维度中,具有离散和连续对称性的模型从远程顺序的存在开始显示出不同的物理属性。在这项工作中,通过添加拓扑挫败感,具有离散局部对称性为特征的抗铁磁$ xyz $ spin链,在参数空间中开发了一个区域,该区域模拟了具有连续对称性的模型的特征。例如,挫败感截断了质量差距,我们描述了具有不同量子数,低能状态的有限量(费米)动量的基态之间的连续交叉,以及有限顺序参数的消失。此外,我们观察到非平凡的基态退化性,非拼接手性和基态忠诚度的奇异叶子。在这个手性区域和相图的其余部分之间的边界之间,能量衍生物的任何不连续性都在热力学极限下消失。
Especially in one dimension, models with discrete and continuous symmetries display different physical properties, starting from the existence of long-range order. In this work, we that, by adding topological frustration, an antiferromagnetic $XYZ$ spin chain, characterized by a discrete local symmetry, develops a region in parameter space which mimics the features of models with continuous symmetries. For instance, frustration closes the mass gap and we describe a continuous crossover between ground states with different quantum numbers, a finite (Fermi) momentum for low energy states, and the disappearance of the finite order parameter. Moreover, we observe non-trivial ground state degeneracies, non-vanishing chirality and a singular foliation of the ground state fidelity . Across the boundary between this chiral region and the rest of the phase diagram any discontinuity in the energy derivatives vanishes in the thermodynamic limit.