本實驗中採用雙層薄膜Bi2Se3/YIG的結構，研究以拓樸絕緣體Bi2Se3作為自旋流偵測層，並量測spin pumping的實驗。
　　首先成長出良好結構及磁性的磁性絕緣層YIG，再於上方成長最佳化成長參數後的Bi2Se3層，以自旋幫浦電壓訊號、電性及薄膜結構作為參數調整之依據，並量測其自旋幫浦的電壓訊號。而後進行固定YIG厚度並改變Bi2Se3層厚度，觀察電壓訊號的變化，並選取訊號較明顯且轉換效率亦高的Bi2Se3厚度作Sb(Antimony)的摻雜變化，在本實驗中是選定12nm的Bi2Se3做摻雜。
　　在變化Sb摻雜量的自旋幫浦量測中，觀察隨摻雜量而改變的電壓訊號，並推測可能影響原因來自電阻值變化、界面處差異性、載子濃度改變、摻雜的取代機制等等。於本實驗中推測，其中最主要影響機制應為摻雜對電阻值的影響及摻雜的取代行為影響了整體的SOC強度，並以此說明為何摻雜後電壓訊號會上升及自旋流與電流間轉換效率會隨摻雜量增加而下降的現象。

Spin pumping is a mechanism that generates spin currents from ferromagnetic metal (FM) and injects into normal metal (NM), while we can detect ISHE voltage signal in the NM layer. We choose Y3Fe5O12 (YIG) grown on Gd3Ga5O12 (GGG) as ferromagnetic metal insulator (FMI) layer, and Bismuth Selenide (Bi2Se3) as NM layer which transfers pure spin current into charge current. We changed the thickness of Bi2Se3 in this experiment, and choose the appropriate thickness to adulterate Antimony (Sb), while doping Sb is used as decreasing the carrier concentration and increasing the thin film resistance in Bi2Se3. We observed the changing of spin pumping voltage signal after doping Sb, and discussed the origin of changing in spin pumping signal.
In our experiment, we observed two results after doping Sb in Bi2Se3, for one thing, the spin pumping voltage has increased, and for another thing, the spin current conversion efficiency has decreased. This consequence might come from the changing of film resistance and Sb substituting in Bi site.
After all, we get high spin current conversion efficiency in Bi2Se3 system, and get high spin current detection efficiency in Sb-doped Bi2Se3 system. This experiment shows that topological insulators with strong spin-orbit coupling could be used in spintronic devices at room temperature.

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