本研究中，利用自旋幫浦在室溫下探討Py / Bi2Se3和Py / Bi2Se3 / WSe2的自旋電荷轉換效率，Bi2Se3是量子材料中的拓樸絕緣體(TI)，具有高自旋軌道耦合(SOT)，並透過其能量產生的拓樸表面態(TISS)因時間反演對稱性的保護。另一方面，WSe2為二維過渡金屬二硫屬化物 (TMDs)，擁有高SOT與缺乏反演對稱性的晶體結構特性，且具有Rashba自旋劈裂(Rashba spin-splitting)形成Rashba 介面。這兩者材料都可透過Inverse Rashba-Edelstein effect (IREE)來產生自旋電荷轉換效率。我們探討不同層數的Bi2Se3在自旋電荷轉換效率上的不同，並來探討Bi2Se3與 WSe2雙層膜結合形成拓樸表面態與Rashba態所混和的表面態的物理性質，且研究其雙層膜的阻尼係數和自旋電荷轉換效率，發現表面態的改變會影響其轉換效率。這項研究提供了拓撲絕緣體和 Rashba 界面之間相互作用對自旋電子學的發展影響。

In this study, we reported the efficiency of spin-charge conversion in bilayer Bi₂Se₃/WSe₂ thin films. The spin current is generated via microwave-driven ferromagnetic resonance-based spin pumping. To investigate the physical properties of Bi₂Se₃/WSe₂ bilayer, the structure of Bi₂Se₃/WSe₂ bilayer displayed the excellent crystalline with XRD and Raman spectra. We examined the spin-to-charge conversion in the Bi₂Se₃ thin films and Bi₂Se₃/WSe₂ bilayer. Our findings revealed the spin-to-charge conversion efficiency of Bi₂Se₃/WSe₂ bilayer was lower than that of Bi₂Se₃ thin films. Furthermore, the ARPES results indicated that the topological surface state (TSS) in bilayer Bi₂Se₃/WSe₂ is disrupted. At the interface, the proximity between Bi₂Se₃’s topological surface states and WSe₂’s electronic states can lead to hybridization, which can have altered dispersion relations and modified spin textures compared to pristine Bi₂Se₃. Therefore, the reduction in spin-to-charge conversion efficiency mainly was attributed from the destruction of topological surface states of Bi2Se3.

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