论文标题
Moiré材料中的矩和多重：旋转瓦利模型的伪用功能重新归一化组
Moments and multiplets in moiré materials: A pseudo-fermion functional renormalization group for spin-valley models
论文作者
论文摘要
对Moiré系统中强相关状态的观察已重新引起了具有较高SU（4）自旋对称性的磁系统的概念兴趣，例如描述莫特绝缘子，其中当地时刻是自由度的自由度。在这里，我们讨论了一个数值重新归一化组方案，以探索基于伪用水的表示，在零温度下的自旋谷有序和非常规的自旋valley液态的形成。我们对$ \ Mathfrak {su} $（2）的常规伪屈光度功能恢复型组方法的概括能够治疗通用的Spin-Valley交换Hamiltonians在$ \ Mathfrak $ \ Mathfrak的自共轭代表中的对角线和非对角线耦合。为了达到适当的数值效率，我们在流程方程上得出了许多对称约束，这些方程显着限制了要求解的普通微分方程的数量。作为一个示例系统，我们研究了对角SU（2）$ _ {\ textrm {spin}} $ $ \ otimes $ u（1）$ _ {\ textrm {valley}} $模型在三角晶格上，该模型在Spin and Valley订购相的富阶段。
The observation of strongly-correlated states in moiré systems has renewed the conceptual interest in magnetic systems with higher SU(4) spin symmetry, e.g. to describe Mott insulators where the local moments are coupled spin-valley degrees of freedom. Here, we discuss a numerical renormalization group scheme to explore the formation of spin-valley ordered and unconventional spin-valley liquid states at zero temperature based on a pseudo-fermion representation. Our generalization of the conventional pseudo-fermion functional renormalization group approach for $\mathfrak{su}$(2) spins is capable of treating diagonal and off-diagonal couplings of generic spin-valley exchange Hamiltonians in the self-conjugate representation of the $\mathfrak{su}$(4) algebra. To achieve proper numerical efficiency, we derive a number of symmetry constraints on the flow equations that significantly limit the number of ordinary differential equations to be solved. As an example system, we investigate a diagonal SU(2)$_{\textrm{spin}}$ $\otimes$ U(1)$_{\textrm{valley}}$ model on the triangular lattice which exhibits a rich phase diagram of spin and valley ordered phases.
