具有六角蜂巢晶格結構的二維材料（例如：石墨烯以及2H族過渡金屬二硫族化物）所蘊含的特殊物理性質，可做為未來對基礎材料科學、電子元件應用，以及資訊傳輸領域應用當中的替代選擇。於部分六角蜂巢晶格的二維材料當中，其特殊晶格結構以及原子軌域組合，除了賦予材料空間反轉對稱破壞性以及時間反轉對稱性外，還分別授予坐落於K以及K’點處之布洛赫函數於單位晶格內具有兩方向相反的內稟環狀電流。由於其方向相反，對於載子而言則是多出了有別於一般電子自旋的能谷電子自由度（valley DOF）。
由於此種能谷電子自由度對應了相反方向的能谷磁矩，於光學應用上則是對於不同圓偏振光有著不同的選擇規則。此種電子與晶格原子之間的交互作用，亦可以推廣應用至量子資訊領域。於量子資訊領域中，以量子位元作為運算基本單位，其中量子位元可以是任意二能階系統，例如:電子自旋、離子阱和超導量子位元等等。超導量子位元則是以電路結構作為基礎打造而成的人造原子系統，其中Google和IBM團隊已投入大量研究經費鑽研其富含的物理特性。隨著二維材料與量子資訊興起，是否能將二維材料獨特之特性應用至超導量子位元系統中，是一個尚未被驗證的議題。
因此，本學位論文將探討二維超導材料2H-二硒化鈮(NbSe2)之特性及在量子計算領域中的應用性。將呈現: (1)基本材料特性，(2)透過圓偏振拉曼光譜分析2H- NbSe2內稟能谷電子耦合自旋電子特性，(3) 2H-二硒化鈮超導電子以及對應量子傳輸特性，及(4) 基於2H-二硒化鈮超導量子位元微波特性，並加以分析討論。此項工作有助於作為研究二維材料超導量子位元的基礎。

2D materials with hexagonal-honeycomb modifications, e.g., graphene systems, and 2H-TMDCs provide alternative options for materials science, electronics, and information processing applications. The special atomic structures in such the system endow the electronic properties with broken-spatial inversion symmetry coupled with time-reversal symmetry that generates system individual valley degree of freedom (DOF) in close analogy to typical spin DOF but with significant differences. The phase winding of Bloch functions around K and K’-points generates intracellular current circulation flowing within the plane results in the distinct valley magnetic moment between K and K’-valleys. This fact features the phenomenon of valley-dependent interband transitions with different circular polarized light.
The interaction between electrons and atoms would probably provide other properties in carrier propagations, optical selection rules, or can even extend to the field of quantum information processing. Furthermore, artificial superconducting qubits commonly incorporate Josephson tunneling junctions as the elementary blocks for scalable quantum information processing and have widely been studied over several groups, including Google and IBM, over the world. With the rise of 2D materials, it would be practical to answer if 2D material can be properly incorporated into this field.
Therefore, this thesis would aim at the investigations of the fundamental properties of 2H-NbSe2, and evaluate the possibilities that adopts 2H-NbSe2 as the material platform for the realizations of superconducting qubit based quantum information processing. The detailed demonstrations of (i) basic material characterizations, (ii) circularly polarized Raman spectroscopy, (iii) electrical transport measurement, and (iv) RF-characterizations of 2H-NbSe2 based superconducting qubit, will be comprehensively discussed. These efforts can be considered as the foundations for the exploration of 2D materials-based superconducting qubits.

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