在本實驗中，先利用分子束磊晶系統(Molecular Beam Epitaxy, MBE) 成長良好的(Sb1-xBix)2Te3薄膜，隨著調控MBE的流量比率來成長這個三元的拓樸絕緣體(Topological insulators, TIs)薄膜，再利用脈衝雷射沉積儀(Pulsed Laser Deposition, PLD) 在拓樸層上蓋鎳鐵合金(Ni80Fe20, Py)層形成雙層結構，並在室溫下將該樣品應用至自旋幫浦系統中，量測其鐵磁共振訊號以及電壓訊號，並計算這個系統的自旋流轉電流的轉換效率，隨著Bi摻雜比例的變化，此拓樸絕緣體的費米能階(Fermi level)位置也會隨之改變，因此實驗中想要探討當費米能階變化時此系統的轉換效率會有什麼改變，而最後結果證實藉由細微地調控TI的費米能階位置會是造成轉換效率最大化的因素。

In this thesis, we use the topological insulator thin films (Sb1-xBix)2Te3 ternary compounds of different Bi-doped ratio and then grow permalloy (Py, Ni80Fe20) on these topological insulators to do the spin pumping experiment at room temperature. By systematically varying x in (Sb1-xBix)2Te3 thin films, the Fermi level position of their electronic band structures will change and can be observed by ARPES. The results show that when the Fermi level closes to Dirac point the spin to charge conversion efficiency, characterized by the inverse Edelstein effect length λIEE, would reach maximum.

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