本研究聚焦於拓樸光子學中拓樸波導在非理想結構與缺陷條件下的能量傳遞與抗散射特性。隨著拓樸物理於電子系統中的快速發展，光學領域亦發展出拓樸光子絕緣體（PTI）與拓樸波導（Topological Waveguide）等概念，實現具方向性與高穩定性的導波傳輸。為探討其實用性與設計彈性，本研究以 zigzag 與 armchair 彎折結構為例，並進一步導入挖空型空氣缺陷、金屬缺陷與矽（Si）材料缺陷等不同類型障礙，模擬其對邊緣態傳遞的影響。透過三維有限時域差分法（FDTD）分析場分布與能量衰減行為，系統性評估不同結構變異對拓樸邊緣態穩定性的影響，期望提供未來拓樸波導元件設計的理論參考。

With the rapid development of topological physics in electronic systems, concepts such as photonic topological insulators (PTIs) and topological waveguides have emerged in optics, enabling highly directional and robust wave propagation. To explore their practical applicability and design flexibility, this research investigates waveguide configurations with zigzag and armchair bends, and introduces various types of defects, including air voids, metallic inclusions, and silicon (Si) material disturbances. Using three-dimensional finite-difference time-domain (FDTD) simulations, we analyze field distributions and energy attenuation to systematically evaluate the impact of structural variations on the one way propagation property of topological edge states. The findings aim to provide theoretical guidance for the future design of robust topological photonic devices.

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