本實驗中，是以MBE系統成長Bi2Te3於sapphire（0001）基板上，利用RHEED、XRD確認晶格、以及AFM做表面粗糙度的量測，確認薄膜的品質，且以sputter系統成長Py層，並在室溫下利用自旋幫浦（spin pumping）系統，在樣品上提供外加磁場和微波使鐵磁層發生鐵磁共振，此Py層傳遞一自旋角動量往Bi2Te3層，即為自旋流，而自旋流可在Bi2Te3層發生反轉自旋霍爾效應（Inverse spin Hall effect,ISHE），是為自旋幫浦。此文中掌握Bi2Te3為拓樸絕緣體的特殊量子效應，其表面態(Topological surface state)有更強的自旋耦合效應及自旋動量耦合效應等等優勢，故以此作為研究材料。為增加自旋流轉電流的效率，我們在介面加入銅傳輸層隔絕鐵磁層的磁性以保護拓墣表面態，並且在數據中發現明顯的電流增益，進而去改變銅厚度變化實驗，探討不同的銅層厚度在奈米尺度下自旋電荷的轉換效應。

This experiment, Bi2Te3 was grown on the sapphire (0001) substrate by the MBE system, the energy band structure was determined by ARPES, the lattice was confirmed by XRD, and the surface roughness was measured by AFM to confirm the quality of the film, and the sputter system was used for growth Py layer, then using a spin pumping system at room temperature to provide an external magnetic field and microwave on the sample to generate ferromagnetic resonance in the ferromagnetic layer, this Py layer transfering a spin angular momentum to the Bi2Te3 layer, is spin current. However the spin current will generate the Inverse spin Hall effect (ISHE) in the Bi2Te3 layer, which is a spin pumping. This thesis grasps the special quantum effect of Bi2Te3 as a topological insulator, and its topological surface state has the advantages of stronger spin orbital coupling effect and spin-momentum coupling effect, so it is used as a research material. In order to increase the efficiency of spin current transfer, we added a copper transport layer to the interface to isolate the magnetism of the ferromagnetic layer to protect the topological surface state, and found an obvious current gain in the data. We discuss the spin-to-charge conversion effect of copper layer with different thickness at the nanoscale.

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