梁啟德臺灣大學：物理研究所王宏軒Wang, Hong-SyuanHong-SyuanWang2007-11-262018-06-282007-11-262018-06-282004http://ntur.lib.ntu.edu.tw//handle/246246/54593本論文研究砷化鎵二維電子系統之傳輸特性及氮砷化銦鎵單量子井結構之光學性質。內容包括以下三部分: 1.高遷移率之砷化鎵系統的電阻峰值特性: 我們呈現在外加垂直磁場下的電子傳輸特性。我們發現電阻的峰值隨著磁場變大而線性增加，直到電子自旋分裂才打破這種現象。這種有趣的現象可以利用量子擴散模型提出完美的解釋，且Coleridge認為利用量子擴散模型可以估計電子的量子生命週期。除此之外，我們觀察到不論是用量子擴散模型或SdH理論所估算的量子生命週期，和溫度都有相同的依賴關係。它暗示著量子擴散模型及SdH理論對我的樣品而言需要進一步修正，且我們猜測修正項或閉O由於熱擾動所造成的。 2.分數量子霍爾平台的偏移: 眾所皆知的如果樣品中含有等量的正負雜質，古典的霍爾效應電阻值This dissertation describe the measurements on the electron transport in two-dimensional GaAs/AlGaAs electron systems and optical properties of InGaAsN/GaAs single quantum well with different nitrogen content. This dissertation consists of the following three parts. 1. Peak values of resistivity in a high-mobility GaAs/AlGaAs electron system We presented magneto transport measurements on a high-quality GaAs electron system. We found that the peak values of resistivity increase linearly with magnetic field and break down when spin splitting becomes resolved. This interesting phenomena can be well interpreted by the quantum diffusion model and Coleridge argued that we can estimate quantum lifetime using this model. In addition, we also observed quantum lifetime has the same temperature dependence on Shubnikov-de Hass (SdH) theory and quantum diffusion model, it implies SdH theory and quantum diffusion model need to be modified for my sample. We speculate this modification may be due to thermal broadening. 2. Upshift of the fractional quantum Hall plateaus It is now established that if there are an equal number of positively and negatively charged impurities, the quantum Hall plateaus inContents Chapter 1. Introduction 1 1.1 Ⅲ—Ⅴ Semiconductors…….……………………………………....………..…....1 1.2 The GaAs/AlGaAs system…………………………………………………..…….2 1.3 The GaAs 2DEG containing self-assembled InAs quantum dots…………………3 1.4 The InGaAsN/GaAs system ….…………………………..………………..……...5 Chapter 2. Background of fields 9 2.1 Density of states …………………………………………………………..…….9 2.2 Classical Hall Effect ………………………………………..……………….…..13 2.3 Quantum Hall effect ……………………………………………………..…….15 2.3.1 Landau levels………………………………………………………….....…15 2.3.2 Shubnikov-de Haas oscillations …………………………………………18 2.3.3 Edge states …………………………………………………………..…….19 2.3.4 Integer quantum Hall effect ………………………………………………..20 2.3.5 Fractional quantum Hall effect ……………………………………………23 2.4 Photoluminescence (PL)…………………………………………………..…….25 Chapter 3. Peak values of resistivity in a high-mobility GaAs/AlGaAs electron system 31 3.1 Introduction …………………………………………………………….…….…31 3.2 Experiments…………………………………….……………………….……..32 3.2.1 Hall bar pattern…………………….……………………………………..32 3.2.2 Sample Structure…………………………………………………………..33 3.3 Theoretical Calculation………………………………………………….……..34 3.4 Results and discussion ………………………………………………….……..36 3.5 Summary ………………………………………………………………..….….41 Chapter 4. Upshift of the fractional quantum Hall plateaus 43 4.1 Introduction …………………………………………………………….…..….43 4.2 Composite fermions…………………………………………………….…..….45 4.2.1 Landau’s quasi-particles …………………………………………………..45 4.2.2 Fundamental introduction of composite fermions...………………………..45 4.2.3 The filling factor at ν=1/2...………..…………………………………..47 4.3 Experiments ………………………………………………………….……....…49 4.4 Results and discussion ……………………………………………………...……50 4.5 Summary …………………………………………………………………….…..53 Chapter 5. Optical properties of an InGaAsN/GaAs single quantum well with different nitrogen content 55 5.1 Introduction …………………………………………………………………....55 5.2 Experiments …………………………………………………………….………56 5.2.1 Sample preparation………………..……………………………………..56 5.2.2 Experiment apparatus………………………………………………...…..57 5.3 Results and discussion ………………………………………………….……..58 5.4 Summary ………………………………………………………………………..67 Chapter 6. Conclusions 71888724 bytesapplication/pdfen-US氮砷化銦鎵單量子井砷化鎵GaAsInGaAsN Single Quantum Wellthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/54593/1/ntu-93-R91222035-1.pdf