本實驗使用氫原子蝕刻的方式，在拓樸絕緣體薄膜上形成鉍金屬層，先探討Bi2Te3拓樸絕緣體和Bi2Te3拓樸絕緣體/鉍金屬雙層膜兩系統與鐵磁層之間的自旋電荷轉換效率(spin-to-charge conversion efficiency )。經氫原子蝕刻處理後的Bi2Te3表面會形成鉍金屬和Bi2O3混合結構，這種混合結構使得自旋電荷轉換效率顯著提升，原因可能是介面的Rashba自旋軌道耦合(spin-orbital coupling, SOC)增強的因素。
再來我們藉由加入銅(Cu)傳輸層以隔絕鐵磁層之磁性交互作用影響以保護拓樸表面態，改變不同的銅層厚度做一系列的實驗探討銅傳輸層對自旋電荷轉換效率的影響。分別在Bi2Te3/Py和Bi2Te3/鉍金屬/Py介面插入不同厚度的銅傳輸層，發現插入銅傳輸層皆使兩個系統的自旋電荷轉換效率大幅增益，而Bi2Te3拓樸絕緣體/鉍金屬雙層膜系統其轉換效率比純Bi2Te3薄膜系統還大4~6倍。我們研究將有助於開發高效率的自旋電子學元件。

In the study, the hydrogen atoms etching to form a bismuth metal layer on a topological insulator thin film was utilized for exploring the spin-to-charge conversion efficiency between the Bi2Te3 topological insulator Bi metal/Bi2Te3 topological insulator bilayer with the ferromagnetic layer. After hydrogen etching treatment, the surface of Bi2Te3 forms a mixed structure of bismuth metal and Bi2O3. This mixed structure significantly enhances the spin-to-charge conversion efficiency, possibly due to the increasement of Rashba spin-orbital coupling (SOC) at the interface.
We introduced a copper (Cu) transport layer to isolate the magnetism of the ferromagnetic layer and protect the topological surface state, conducting a series of experiments to investigate the effect of varying the Cu layer thickness on spin-to-charge conversion efficiency. Cu transport layers with different thicknesses were inserted between Bi2Te3/Py and Bi2Te3/Bi metal/Py interfaces. It was found that inserting the Cu transport layer significantly increased the spin-to-charge conversion efficiency in both systems, with the conversion efficiency of the Bi metal/Bi2Te3 bilayer system being 4-6 times greater than that of the Bi2Te3 thin film system. Our study will contribute to the development of spintronic devices with high spin-to-charge conversion efficiency.

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