AI 中文总结
研究表明无需全局反演对称性破缺，局部和最小对称性破缺即可诱导拓扑相。利用光子合金平台，通过无序驱动的局部对称性破缺触发QSH和QVH相变，支持相关态。经拓扑表征揭示尺寸依赖缩放行为，为集成拓扑光通信提供新设计策略。
AI 中文摘要
传统方法通过打破整个光子晶体的空间反演对称性来产生量子自旋霍尔（QSH）和量子谷霍尔（QVH）效应。这限制了器件可重构性和制造后适应性。本研究表明全局反演对称性破缺并非诱导拓扑相的先决条件，局部和最小对称性破缺就足够。利用基于平行板波导中随机替代无序的光子合金平台，展示了无序驱动的局部镜面和平面内对称性破缺分别能开启拓扑间隙触发QSH和QVH相变，支持边缘和谷扭结态。通过反射相绕组法的严格拓扑表征揭示了两种配置中显著的尺寸依赖缩放行为。此光子合金平台不仅加深了对无序诱导拓扑物理的理解，还为集成拓扑光通信提供了可扩展、高效的设计策略。
英文摘要
Conventional approaches generate quantum spin Hall (QSH) and quantum valley Hall (QVH) effects by breaking spatial inversion symmetry across the entire photonic crystal. Consequently, modulating the bulk transmission gaps within these periodic frameworks typically requires global modification of structural parameters throughout the lattice, severely limiting device reconfigurability and post-fabrication adaptability. In this work, we demonstrate that global inversion symmetry breaking is not a prerequisite for inducing topological phases. Instead, local and minimal symmetry breaking is sufficient. Using a photonic alloy platform based on random substitutional disorder in a parallel-plate waveguide, we show that a disorder-driven local breaking of z-direction mirror symmetry and a local breaking of in-plane symmetry are capable of opening topological gaps to trigger QSH and QVH phase transitions, respectively, thereby supporting robust helical edge states and valley kink states. Rigorous topological characterization via the reflection-phase winding method reveals a striking size-dependent scaling behavior in both configurations, where the threshold doping concentration required to trigger the topological phase transition asymptotically vanishes in the thermodynamic limit. By enabling flexible, on-demand bulk gap engineering simply through random doping tuning rather than global structural reconfigurations, this photonic alloy platform not only deepens understanding of disorder induced topological physics but also offers a scalable, highly efficient design strategy for integrated topological optical communications.
