Photonic topological structures supporting spin‐momentum locked topological states underpin a plethora of prospects and applications for disorder‐robust routing of light. One of the cornerstone ideas to realize such states is to exploit uniform bianisotropic response in periodic structures with appropriate lattice symmetries, which together enable the topological bandgap. Here, it is demonstrated that staggered bianisotropic response gives rise to the topological states even in a simple lattice geometry whose counterpart with uniform bianisotropy is topologically trivial. The reason behind this intriguing behavior is in the difference in the effective coupling between the resonant elements with the same and with the opposite signs of bianisotropy. Based on this insight, a one‐dimensional (1D) equidistant array is designed, which consists of high‐index all‐dielectric particles with alternating signs of bianisotropic response. The array possesses chiral symmetry and hosts topologically protected edge states pinned to the frequencies of hybrid magneto‐electric modes. These results pave a way toward flexible engineering of topologically robust light localization and propagation by encoding spatially varying bianisotropy patterns in photonic structures.

中文翻译：

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交错双各向异性介导的光子拓扑状态

支持自旋动量锁定拓扑状态的光子拓扑结构为无序鲁棒的光路由提供了许多前景和应用。实现这种状态的基石思想之一是在具有适当晶格对称性的周期性结构中利用均匀的各向异性响应，从而共同实现拓扑带隙。在此证明，交错的各向异性反应即使在简单的点阵几何中也具有拓扑状态，而简单的点阵几何具有均匀各向异性的对应关系。引起这种有趣行为的原因在于，具有相同和相反各向异性的谐振元件之间的有效耦合有所不同。基于此见识，设计了一维（1D）等距阵列，它由高折射率全介电粒子组成，具有交替的各向异性反应迹象。该阵列具有手征对称性，并具有固定在混合磁电模式频率上的受拓扑保护的边缘状态。这些结果通过对光子结构中空间变化的各向异性图案进行编码，为拓扑稳定的光的本地化和传播的灵活工程铺平了道路。