近年來，半導體微縮製程的極限，使其朝向改變閘極結構或開發新的通道材料發展，因此，人們對二維材料的研究開始興起，近期，屬於過渡金屬硫屬化合物且具有扭曲1T’結構的二硫化錸(ReS2)由於其有趣的光學和電子特性而引起了人們的關注。迄今為止，已經有許多對於ReS2的能帶結構以及電流特性的研究，但對於發光特性的了解還不夠透徹。
因此，本論文藉由不同環境溫度下，量測的ReS2光致發光，確定其適合在低溫的環境下工作，並在低溫中量測ReS2 PL的偏振依賴性，研究了不同激子峰的發射是由於不同晶格方向的電子-電洞對複合所產生，而材料照光吸收的部分，受到晶格結構各向異性的特點，對於沿Re-Re金屬鍵方向偏振的光吸收較率較高。接著，透過轉移矩陣法結合ReS2激子的特性來對照光致發光激發(PLE)的實驗，發現了在發射光譜中，多個激子發射峰的出現，是由於光子被限制在ReS2材料內部，造成極化子與激子的耦合，導致主要的兩個激子峰分裂，而ReS2材料厚度發生變化時，相當於共振腔光子模態改變，會使吸收光譜受到影響，因而對於不同波長光源激發展現出相異的特性。
這些發現促進了對於ReS2的光致發光光學性質的理解，有利於未來位於近紅外波段，具有偏振特性的新穎奈米電子元件開發，並可延伸至其他二維材料進行異質結構的整合。

ReS2 which owns the exotic optical and electrical properties has attracted great attentions. Currently, multiple works have theoretically investigated its electronic band structure and experimentally explored its electrical transport properties. But the luminescence characteristics of ReS2 remains largely unexplored. In this thesis, we perform polarization resolved photoluminescence measurements on ReS2 at cryogenic temperature. Our result reveals multiple excitonic peaks, which are originated from the recombination of electron-hole pairs in different lattice directions (anisotropic crystal structure of ReS2). In addition, we observe that the exciton peaks measured from the thicker ReS2 flakes could exhibit the splitting behaviors. Our numerical simulation (transfer matrix method) together with the photoluminescence excitation (PLE) experiments indicate that the splitting is caused by the coupling between polarons and excitons. Critically, our results not only show the evidence of strong light-matter coupling of ReS2, but also suggest its usefulness to novel nanophotonics applications.

致謝 i
摘要 iii
Abstract iv
目錄 v
圖目錄 vii
第一章 緒論 1
第二章 二硫化錸(ReS2)的發光以及電子特性 5
2.1 ReS2晶格結構 6
2.2 ReS2的電特性 7
2.3 光致發光(Photoluminescence, PL) 8
2.3.1 ReS2的厚度相依性 9
2.3.2 ReS2的溫度相依性 11
2.3.3 ReS2的偏振相依性 12
2.3.4 極化子-激子耦合(Polaritons-excitons coupling) 13
第三章 ReS2樣品量測結果 17
3.1 二維材料的製備 17
3.1.1 晶圓清洗 17
3.1.2 機械剝離法 17
3.2 ReS2的光致發光量測 18
3.2.1 ReS2光致發光的溫度依賴性 20
3.2.2 ReS2光致發光對入射光功率的光響應 22
3.2.3 ReS2光致發光對線性入射光偏振的光響應 23
3.2.4 ReS2的線性偏振光致發光與各向異性的發射特性 24
3.3 ReS2的光致發光激發實驗 25
第四章 ReS2的微型共振腔模擬 30
4.1 轉移矩陣法(Transfer matrix method) 30
4.2 激子-共振腔光子耦合(Exciton-cavity photon coupling) 33
4.3 模擬與實驗結果 35
4.3.1 ReS2光致發光激發實驗對應模擬 35
4.3.2 ReS2光致發光對應模擬 37
第五章 結論 39
參考文獻 40

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