在本論文中，中使用兆赫波時間解析系統（THz-TDS）獲得太赫茲範圍內的GaSe1-xSx樣品的光學和電學性質。 結果表明，隨著硫含量的增加，GaSe1-xSx樣品的性質接近GaS的性質。 這種行為與由於硫摻雜導致的GaSe1-xSx樣品的堆疊類型轉變有關。 所有樣品的獲得折射率範圍為3.0至3.3。 隨著硫含量的增加，GaSe1-xSx樣品的吸收和電導率增加。 從Drude模型擬合中，獲得的載流子濃度範圍為0.7×1015cm-3至2.3×1015cm-3，隨著硫含量的增加而減少，而獲得的遷移率範圍為81cm2 /V⸱s至233cm2 /V⸱s，隨著硫含量的增加而增加。

The optical and electrical properties of GaSe1-xSx samples in the terahertz range were obtained using terahertz time-domain spectroscopy (THz-TDS). Results showed that the properties of the GaSe1-xSx samples approach that of GaS as the amount of sulfur increases. This behavior is linked to the stacking type transition of the GaSe1-xSx samples due to sulfur doping. The obtained index of refraction ranges from 3.0 to 3.3 for all samples. The absorption and conductivity of the GaSe1-xSx samples increases as the sulfur content increases. From the Drude model fitting, the obtained carrier concentration ranges from 0.7x1015 cm-3 to 2.3x1015 cm-3, decreasing as the amount of sulfur increases, while the obtained mobility ranges from 81 cm2/V⸱s to 233 cm2/V⸱s, increasing as the amount of sulfur increases.

論文審定書 i
論文授權書 ii
Acknowledgements iii
摘要 iv
Abstract v
List of Figures vii
List of Tables ix
Chapter 1 Introduction 1
1.1 Background of the study 1
1.2 THz radiation 2
1.3 Generation of THz radiation 4
1.4 Developments in THz research 6
1.5 Sulfur doping in GaSe 8
Chapter 2 Generation of terahertz pulses from a biased photoconductive antenna 18
2.1 The physics of the PC antenna 18
2.2 Detection of THz radiation generated from a biased PC antenna 21
Chapter 3 Terahertz time-domain spectroscopy experimental set-up and calculation 25
3.1 Experimental Set-up 25
3.2 Theoretical background 27
Chapter 4 Sample information and Data analysis 31
4.1 Sample information 31
4.2 Data analysis 33
Chapter 5 Conclusion 50
References 52

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