本研究將槽孔天線與光子拓樸絕緣體整合，構築出一種拓樸波導饋入槽孔天線的結構，以利用拓樸邊緣態實現電磁波的單向傳輸並抑制背向散射。經由點波源與偽自旋激發，結果顯示當激發頻率超越邊緣態的交合點時，能量傳輸方向可逆轉，且背向散射顯著減弱。能帶結構分析則發現，加入槽孔天線後，平凡（trivial）與非平凡（non-trivial）晶格的能隙分別增大約 6.2 倍與 2.7 倍；在 a/R=3.0 下，原本應閉合之能帶仍保持分裂，導致拓樸相變無法完成，邊緣態因此消失，顯示目前所使用之槽孔天線因不具 C6 對稱而破壞了狄拉克錐的對稱性。儘管如此，只要在能隙內適當選擇激發頻率並放置天線於晶格適當位置，即可在無完全拓樸保護的情況下仍達到顯著的背向散射抑制。

This study integrates a slot antenna with a photonic topological insulator to form a topological waveguide fed slot-antenna structure, leveraging topological edge states for unidirectional electromagnetic wave transmission and back-scattering suppression. Excitation by both point-source and pseudospin inputs reveals that, when the excitation frequency exceeds the edge-state crossing point, the direction of energy flow at the slot reverses and back-scattering is significantly reduced. Band-structure analysis shows that embedding the slot antenna enlarges the bandgaps by approximately 6.2 times in trivial lattices and 2.7 times in non-trivial lattices; at a/R=3.0, bands that should close remain split, preventing the topological phase transition and causing the edge states to vanish and lose topological protection. Nevertheless, by selecting an excitation frequency within the bandgap and placing the antenna appropriately within the lattice, pronounced back-scattering suppression can still be achieved even without full topological protection.

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