论文标题
光子thue-morse准晶体中的高阶拓扑状态：四极杆绝缘子和角落状态的新起源
Higher-order topological states in photonic Thue-Morse quasicrystals: quadrupole insulator and a new origin of corner states
论文作者
论文摘要
高阶拓扑绝缘子（HOTIS）中的角状态（CSS）最近对晶体和准晶体都引起了极大的兴趣。与电子系统相反，在光子准晶体（PQC）中尚未发现HOTIS。在这里，我们从系统地研究了二维Thue-Morse光子准晶体（TM-PQC）中的高阶拓扑。不仅是由多极矩引起的分数电荷的拓扑相变和非平凡的CS，而且由于拐角附近的TM-PQC的复杂结构，还发现了一种新型的CSS。这些CSS的不同起源也基于紧密结合模型进行分析。我们的工作打开了探索光子晶体以外的富含热物理的大门，并且PQC中CSS的鲁棒性显示了应用的潜力。
Corner states (CSs) in higher-order topological insulators (HOTIs) have recently been of great interest in both crystals and quasicrystals. In contrast to electronic systems, HOTIs have not been found in photonic quasicrystals (PQCs). Here, we systemically study the higher-order topology in the two-dimensional Thue-Morse photonic quasicrystals (TM-PQCs). Not only the topological phase transition and the non-trivial CSs with fractional charge induced by multipole moments, but also a new type of CSs are found due to the complex structure of TM-PQCs near corners. The different origins of these CSs are also analyzed based on the tight-binding model. Our work opens the door to explore richer HOT physics beyond photonic crystals and the robustness of CSs in PQC shows the potential for applications.
