6-1 結論
最後，總結本論文所做的實驗以及觀察到的現象，可以歸納出，利用帶有軌道角動量的 光，確實可以改變磁性材料的磁性行為，並且，可以使用層間交換耦合系統的材料，以及鐵 磁層-二維材料的磁耦合材料，記錄下渦旋光所造成的變化。首先，在鉑/鈷/釕/鈷/鉑這樣的 層間交換耦合系統，先觀察到沿著長軸的磁滯曲線，從鐵磁性轉變為順磁性，這樣的變化是 可靠並且可重複觀察到的，且要觀察到此變化，輸入光的功率及渦旋光的軌道角動量是具有 門檻的，小於門檻的光以及線性偏振的光皆無法觀察到轉變。接著，角度的磁性分析顯示，
此材料的 MA 於照光的前後有顯著的不同，原本的磁易軸座落於樣品的長軸上，照光後的 磁易軸會偏轉到另一個方向上。更進一步探討軌道角動量的正負兩個自由度對於樣品磁易 軸的造成如何的偏轉，以及發現使用垂直外加磁場可以重設渦旋光造成的偏轉。實驗數據的 第二部分，將上述之實驗推廣至鈷-二硫化鉬這類的鐵磁性-二維材料異質介面上，該系統因 為鈷-硫之間的鍵結而也有鐵磁性的耦合現象，結果發現，渦旋光也可以改變此類材料的磁 各向異性。這些實驗告訴我們，帶有軌道角動量的光有很大的潛力被應用在「磁-光儲存元 件」上
6-2 未來展望
由於二維材料 MoS2 其本身因為結構上的對稱性破壞以及鉬原子具有強自旋軌道耦合 的特性，其半導體的能帶有自旋偏極化的特性以及對於激發光的自旋具有選擇性等等許多 有趣的特性，因此，若能仔細思考二維材料的性質，將之整合進自旋電子學的範疇，再加上 本實驗所使用的渦旋光，可以預期將來很有可能有更多具有創意的研究與應用。目前已經得 知，Co/MoS2系統也可以紀錄渦旋光造成的磁性變化，因此，未來的研究可以繼續發展下去，
將鐵磁性金屬例如鈷，鍍在MoS2上並做成霍爾電極，可以用渦旋光來操控或記錄磁性，也 可以作成自旋電子元件的形式，例如用渦旋光操控的自旋閥，或者使用其他二維材料進行測 試，找到更搭配的組合。本實驗所揭示的物理現象，希望能為自旋電子學與二維材料以及光 學三個方面的結合帶來貢獻。
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