论文标题
广义旋转轨耦合su-schrieffer-heeger模型的拓扑特性
Topological properties of a generalized spin-orbit-coupled Su-Schrieffer-Heeger model
论文作者
论文摘要
从理论上讲，我们探讨了间和细胞内旋转轨道耦合对具有多部分晶格结构的广义Su-Schrieffer-Heeger模型的拓扑特性的影响，该模型包含每个单位单元格的位置均匀数量。我们表明，自旋轨道耦合丰富了拓扑相图，因此参数空间中的非平凡拓扑区域显着扩展，这适用于潜在的应用。我们提供了一个分析公式，该公式是根据sublattice数字信号传导的分析公式，即在托管双重/四倍变性零模式边界状态的参数空间中有两个非平凡的拓扑阶段。我们还发现，通过增加单位单元内的sublattices的数量，拓扑相图的非平凡区域包括两双退化的零模式边缘状态急剧扩展。我们的对称研究表明，晶格方向上的U（1）旋转旋转对称性是出现四倍退化零模式边界状态的关键成分。
We explore theoretically the effect of inter and intra cell spin-orbit couplings on topological properties of a generalized Su-Schrieffer-Heeger model with multipartite lattice structure containing even number of sites per unit cell. We show that the spin-orbit couplings enrich topological phase diagrams so that nontrivial topological regions in the space of parameters extend significantly which is suitable for potential applications. We present an analytical formula for winding number in terms of sublattice number signaling that there are two nontrivial topological phases in the space of parameters hosting twofold/fourfold degenerate zero-mode boundary states. We also find that by increasing the number of sublattices within unit cell, the nontrivial regions of topological phase diagram including twofold degenerate zero-mode edge states extend dramatically. Our symmetry investigation shows that U(1) spin rotational symmetry around the lattice direction is the crucial ingredient for the appearance of fourfold degenerate zero-mode boundary states.
