本研究主要探討扶手椅石墨烯奈米帶（AGNRs）異質結構的電子傳輸特性，聚焦於 9-7-9 AGNR 異質結構中的拓撲態（Topological States）。研究發現，拓撲態與傳導帶及價電帶的子帶明顯隔離，確保電子主要在拓撲態內傳輸，降低連續態電子對傳輸的影響，同時提升拓撲態的穩健性。為了探討異質結構中拓樸態的電子傳輸特性，本研究在異質結構中引入結構空缺，並施加局部閘極電壓，分析其對拓樸態能階與傳輸行為的影響。結果顯示，拓樸態具有良好的穩健性，能在缺陷存在或外部電場調控下維持穩定傳輸。此外，透過調整結構參數與控制拓樸
態與電極之間的耦合強度，我們觀察到拓樸態間的電子躍遷強度與庫倫交互作用變化，進一步揭示拓樸態傳輸機制的細節。研究結果驗證了AGNR 異質結構中拓樸態在控制電子傳輸方面的穩定性，為未來應用於穩健型電子元件提供了理論依據與參考。

This study mainly investigates the electron transport properties of armchair graphene nanoribbons (AGNRs) heterostructures, focusing specifically on the topological states within a 9-7-9 AGNR heterostructure. It was found that the topological states are significantly isolated
from the subbands of the conduction and valence bands.This isolation ensures that electrons predominantly transport within the topological states, minimizing interference from bulk-state electrons and simultaneously enhancing the robustness of the topological states. To investigate the electronic transport properties of topological states in heterostructures, this study introduces structural vacancies and applies local gate voltages to a heterostructure. The effects on the energy levels and transport behavior of the topological states are analyzed. The results demonstrate that the topological states exhibit strong robustness, maintaining stable transport in the presence of defects and external electric field modulation. Moreover, Through structural design and modulation of the coupling characteristics between the topological states and the
electrodes, variations in the electron hopping strength and Coulomb interactions between the topological states are observed, further revealing the underlying transport mechanisms. These findings confirm the stability of topological states in AGNR heterostructures for controlling
electron transport and provide theoretical support and reference for the design of robust electronic devices in the future.

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