由於二維材料的表面積大、結構穩定，以及容易調變能帶結構等優點，近年來，越來越多的團隊投入到這樣的研究當中，其中錳硫族磷酸鹽MnPX3在單層下為直接能隙且帶有反鐵磁性質，因此非常適合應用於催化、電子自旋元件或儲能元件上。

在本論文中，我們利用了各種光學系統量測新穎的反鐵磁二維材料。X光繞射及拉曼光譜皆顯示出晶體良好的結晶情況及穩定的結構，吸收與反射光譜則是確定了材料的能隙位置，MnPS3於2.51 eV、MnPS3於1.97 eV，並且首次發現個位數層數下MnPS3的螢光發光，中心波長於521 nm，半高寬僅15 nm。

除此之外還有利用鑽石高壓砧進行高達40 GPa的變壓拉曼量測，在非靜水壓的環境下，觀察到MnPS3於26 GPa，MnPS3於20 GPa下由半導體轉為金屬態的變化，以及環境對於金屬化壓力點的影響。

A sizeable chemical reaction surface area, stable structure, and ease of modulating the energy band structure are the advantages of two-dimensional (2D), so a growing number of research groups have been dedicated to this theme in recent years. The monolayer of transition metal trichalcogenides is a direct bandgap semiconductor with antiferromagnetic properties. Therefore, it is very promising for application in catalysis, electron spin devices, or energy storage devices. Among them, transition-metal phosphorus chalcogenides (MPX3) have attracted great interest because of their unique magnetism properties in low-dimensional systems.

In this thesis, various optical measurements were employed to explore the physical properties of MnPX3. The X-ray diffraction and Raman scattering measurements show good crystallinity and stable structure. The optical absorption and reflection spectra measurements could determine the energy bandgap of the bulk MPX3 material. The band gap of MnPS3 and MnPS3 are at 2.51 eV and 1.97 eV, respectively. The photoluminescence results of MnPS3 show the intraband transition for bulk sample. The band-to-band emission of the few-layer MnPS3 located at 521 nm (~2.38 eV) was observed for the first time.

Moreover, the pressure-dependent Raman scattering measurements were performed using the diamond cell anvil. Under the non-hydrostatic state, we found the phase transition from semiconductor to the metallic state of MnPS3 and MnPSe3 around 27 and 21 GPa, respectively. We discuss the influence of the environment on the metallization pressure point.

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