本次實驗我們將在室溫的情況下，探討 MoS2 在自旋幫浦系統中的自旋電荷轉換效率，MoS2 為二維過度金屬硫化物（TMDs），先前也已經被廣泛地用於自旋電子學的討論中，且因為其在結構上有著反演對稱性的缺乏以及過度金屬的 d 軌域所引起的強大的 SOC，使的 Brillouin zone 中Γ 點產生 Rashba spin-splitting 再形成Rashba interface ， 而 在 此 特 殊 的 介 面 條 件 中 ， 我 們 可 以 利 用 Inverse Rashba-Edelstein effect 來計算得到 MoS2 的自旋電荷轉換效率。我們將比較不同層數 MoS2的自旋電荷轉換效率，我們針對了 1L MoS2 / Py、2L MoS2 / Py 和 3L MoS2 / Py 三組雙層結構進行自旋幫浦研究比較，最終算出自旋電荷轉換效率 Inverse Edelstein length ( ???? ) 分別為2.11 [nm] 、 2.51 [nm] 以及1.54 [nm]。後續還在 1L MoS2 / Py 的界面中插入不同厚度的銅金屬傳輸層，藉此觀察銅金屬傳輸層對於整體樣品的自旋電荷轉換效率的影響，最終發現銅傳輸層能夠使 MoS2 / Py 介面的自旋電荷轉換效率大幅上升，並達到最高 3.27 [nm]。另外，我們還把銅換成氧化鋁作為插入層，藉由調整金屬半導體界面產生的 schottky barrier 來探討其對於 1L MoS2 / Py、2L MoS2 / Py 兩組雙層結構自旋電荷轉換效率的影響，最終算出自旋電荷轉換效率最高可達到分別為2.78 [nm]和2.58 [nm]。

In this experiment, we will investigate the spin-to-charge conversion efficiency of the transition metal dichalcogenide MoS2 in a spin pumping system at room temperature. MoS2 has been widely discussed in spintronics previously. We use permalloy (Py) as the ferromagnetic layer for ferromagnetic resonance and employ the Inverse Rashba-Edelstein effect to calculate the spin-to-charge conversion efficiency of MoS2. We will compare the spin-to-charge conversion efficiencies of MoS2 with different numbers of layers, focusing on 1L MoS2 / Py, 2L MoS2 / Py, and 3L MoS2 / Py double-layer structures for spin pumping research. Subsequently, we will insert copper metal transfer layers of varying thicknesses into the interface of 1L MoS2 / Py, as well as insert aluminum oxide as a transfer layer into both 1L MoS2 / Py and 2L MoS2 / Py double-layer structures, exploring the effects of these two transfer layers on the overall spin-to-charge conversion efficiency of the samples. Ultimately, we find that both copper and aluminum oxide can enhance the spin-to-charge conversion efficiency at the MoS2 / Py interface.

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