高阶光子节环半金属中的反手性铰链态
Antichiral hinge states in a higher-order photonic nodal ring semimetal
浏览论文内容
中文总结 AI 辅助
研究在三维旋磁光子晶体高阶节环半金属中观察反演手性铰链态，通过近场扫描测量发现其单向传播及鲁棒传输特性，空间位置可重构，还观察到相关表面态，扩展了反演手性态并有望用于光子路由。
中文摘要 AI 辅助
反演手性态在相反边界上沿相同方向传播，突破了边界模式必须消除净手性的传统限制。先前发现的反演手性态仅限于一阶拓扑半金属。然而，反演手性铰链态，即最近发现的高阶手性铰链态的反演手性对应物，仍然难以捉摸。在此，我们报告了在由三维旋磁光子晶体制成的高阶节环半金属中观察到反演手性铰链态。近场扫描测量揭示了在两个平行的一维边界处有一对铰链态，它们沿相同方向单向传播，对金属散射体具有鲁棒传输。其空间位置可通过添加或移除光子层重新配置。此外观察到的反演手性和鼓面表面态在单个光子系统中展现出一阶和二阶拓扑边界态的层级结构。我们的工作将反演手性态扩展到高阶拓扑半金属，并在鲁棒和可重构光子路由方面有潜在应用。
英文摘要
Antichiral states propagate in the same direction on opposite boundaries, defying the conventional constraint that boundary modes must cancel net chirality. Previously found antichiral states have been limited to first-order topological semimetals. However, antichiral hinge states, the antichiral counterpart of recently discovered higher-order chiral hinge states, remain elusive. Here, we report the observation of antichiral hinge states in a higher-order nodal-ring semimetal made of a three-dimensional gyromagnetic photonic crystal. Near-field scanning measurements reveal a pair of hinge states at two parallel one-dimensional boundaries propagating unidirectionally along the same direction, with robust transport against metallic scatterers. Their spatial positions can be reconfigured by adding or removing photonic layers. The additionally observed antichiral and drumhead surface states manifest a hierarchy of first- and second-order topological boundary states within a single photonic system. Our work extends antichiral states to higher-order topological semimetals and has potential applications in robust and reconfigurable photonic routing.
