论文标题
拓扑项
Phases of the (2+1) dimensional SO(5) non-linear sigma model with topological term
论文作者
论文摘要
我们使用石墨烯中的半填充的零体Landau水平作为正规化方案，以研究SO（5）在2+1个维度中以Wess-Zumino-witten拓扑术语为准的SO（5）非线性Sigma模型。如Ippoliti等人所示。 [PRB 98，235108（2019）]，这种方法允许进行负面符号辅助量量子蒙特卡洛模拟。该型号具有单个免费参数，$ u_0 $，可以监视刚度。在可访问的参数范围内，无符号模拟，我们观察到一个大$ u_0 $或硬度限制的有序阶段。值得注意的是，降低$ u_0 $后，磁化强度大幅下降，相关长度超过了我们最大的系统尺寸，可容纳100次通量量子。讨论了我们结果对价键固体和抗铁磁铁之间的量子相变的含义。
We use the half-filled zeroth Landau level in graphene as a regularization scheme to study the physics of the SO(5) non-linear sigma model subject to a Wess-Zumino-Witten topological term in 2+1 dimensions. As shown by Ippoliti et al. [PRB 98, 235108 (2019)], this approach allows for negative sign free auxiliary field quantum Monte Carlo simulations. The model has a single free parameter, $U_0$, that monitors the stiffness. Within the parameter range accessible to negative sign free simulations, we observe an ordered phase in the large $U_0$ or stiff limit. Remarkably, upon reducing $U_0$ the magnetization drops substantially, and the correlation length exceeds our biggest system sizes, accommodating 100 flux quanta. The implications of our results for deconfined quantum phase transitions between valence bond solids and anti-ferromagnets are discussed.
