二維材料做為現今熱門固態物理研究主題之一，具有相當大的潛力，
本論文透過二維材料與複雜性氧化物的結合，期望觀察到莫爾超晶格的
物理性質，開創新的研究領域。本研究利用化學氣相沉積法成長過渡金屬
二硫化物，並將其互相堆疊，轉移到鈦酸鍶基板上，製作二硫化鎢/二硫
化鉬、二硫化鎢(二硫化鉬)/鈦酸鍶兩種扭角異質結構，透過拉曼光譜、光
致發光光譜以及二倍頻諧波，研究因其上下層之間的距離不同而變化的
物理性質。在研究中發現過渡金屬硫化物在鈦酸鍶(111)晶面上以不同角
度堆疊時，其拉曼光譜及光致發光光譜皆不與堆疊角度成週期性變化，推
測原因為鈦酸鍶表面的晶格沒有讓過渡金屬硫化物嵌入的空缺，以致於
二維材料與鈦酸鍶基板的距離不會隨扭角做改變，因此兩者的交互作用
不隨著角度變化。對於過渡金屬硫化物與複雜性氧化物的結合，還有更多
的知識可以去探討。

Two-dimensional materials have caught significant attention as one of the most
popular research topics in solid-state physics over the past decade. In this thesis,
through the combination of two-dimensional materials and complex oxides, we
expect to observe the intriguing physical properties caused by the intra-layer
Moiré superlattices.
In this work, transition metal dichalcogenides (TMDCs) were grown by
chemical vapor deposition (CVD). The grown TMDCs were then transferred
onto strontium titanate(SrTiO3, STO) substrates to construct tungsten disulfide
(WS2)/molybdenum disulfide(MoS2), WS2(MoS2)/STO twisted
heterostructures. The combination of Raman spectroscopy, photoluminescence
spectroscopy (PL) and second harmonic generation(SHG) has been employed
to study the physical properties of the twisted heterostructures. Based on the
experimental results, we found that when TMDCs are stacked on STO(111)
with different twist angles, their Raman spectra and PL spectra do not change
periodically with twist angles. We speculate that the main reason is the
atomically-flat top surface of STO substrate has no kink edges to allow
interlayer repulsion/attraction with TMDCs. As a result, neither the interlayer
distance nor the intralayer coupling between TMDCs and STO substrate
changes with different twist angles. In the near future, more efforts shall be paid
to artificially enhance the coupling between 2D materials and complex oxides.

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