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The determination of mass marking methods with high marks retention rate for hatchery-reared fry
No full textBroad-Gain Measurement of Semiconductor Optical Amplifier with Nonidentical Multiple Quantum Wells
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Efficient Peak Temperature Computation with Leakage Power Consideration
No full text隨著現代多核技術在晶片上尋求更多的計算能力, 過熱問題在智慧手機、個人電腦和高端伺服器的晶片設計上是一個關鍵。因此，發展出各式各樣的能源管理演算法在不維背熱能的限制下來達成計算的要求，所有的能源管理機制不僅僅依賴對現下溫度測量，也需考量後面時間點上的溫度預測。然而，多數既存溫度預測演算法假設晶片上的漏電流功率消耗為常數，即並沒有意識在進階多核晶片中越來越重要的漏電流功率對溫度的影響。這篇論文探討溫度和漏電流功率消耗之間在電路上的回饋迴圈機制，並在多核平台上發展出對溫度敏銳的功率模型並提供精確快速的溫度預測。論文所提設的預測策略的好壞將從預測誤差和計算時間等方面來看，由基準測試 (benchmark) 來評估。實驗結果表示出我們的策略比相競爭的類似解法更加精準，能擁有更短的計算時間使得我們的策略適合即時的能源管理演算法。With the modern multi-core technology to explore more computing power in a chip, overheating is now a critical problem of chip designs for smart phones, personal computers, and high-end servers. Therefore, various power management algorithms are developed to meet the computing requirements without violating the thermal constraints, and all of the power management algorithms rely on not only the measurement of the current temperature but also the temperature estimation for the following time points. However, most of the existing temperature estimation algorithms assume that the leakage power consumption of a chip is a constant and are not aware of the impact of temperature on the leakage power consumption which is more and more significant in the advanced multi-core chips. This paper explores the feedback loop between the temperature and the leakage power consumption of a circuit and develops a temperature-aware power model to provide the accurate temperature estimation for multi-core platforms. The performance of the proposed estimation scheme is then evaluated with benchmark suites in terms of the estimation error and the computing time. The experimental results show that our scheme is more accurate than all of the competing solutions, and the short computing time also makes our scheme suitable for real-time power management algorithms
Characteristics and Applications of Semiconductor Lasers and Semiconductor Optical Amplifiers
No full text隨著光通訊領域的發展，以及因應網路的需求和資訊傳輸量的增加，在本論文中我們利用設計過的量子點與量子井結構，來開發具有更寬發光頻寬特性，以及擁有更高直接調變速度、更寬調變頻寬的半導體雷射與半導體光放大器。
首先我們提出一種新的量測寬頻增益的方法，設計出新型的兩段式波導的量子點光放大器，使其可以在不需要外部雷射以及複雜的實驗架設之下，便可以量測到量子點光放大器的增益頻譜，並且得到一個正的增益值超過480nm以上的極寬頻增益，並且最大的增益值可以超過42.83cm-1。
另外，我們也透過實驗上的量測發現了具有第二量子化能階的量子點雷射，因其自由電子在本身傳導帶內部的量子化能階做躍遷，又這兩個能帶間的能隙很小，所以可以放出遠紅外光波段的波長，而目前在遠紅外光這個波段正是欠缺便宜且穩定的波源，想必在未來的發展性勢必相當大。
除此之外，我們藉由控制減短共振腔的長度，增加材料的損耗，或是降低斷面的反射量等方法，使得元件可以在第二量子化能階發出雷射光。我們利用這種發光機制，在實驗結果上發現，操作在第二量子化能階的元件，其頻寬可達2.78GHz，比第一量子化能階的元件高出約2.6倍。這個研究結果對於量子點雷射在直接調變上的應用來講是一個很重要的突破，有助於未來光通訊市場的發展和普及。然而我們更進一步的針對元件內部的載子與放光機制，去做理論上的研究與分析，發展出一套動態模型來解釋實驗結果，關於這部分目前也是尚未被研究討論過的。
最後，我們繼續量測非對稱量子井兩段式波導雷射的頻率響應，因為載子在不同量子井間互相轉移的過程，造成共振波長的快速切換，使得此結構雷射的直接調變速率可以達到更寬的調變頻寬，約6.04GHz，希望藉此來因應將來光通訊市場的發展和普及的需要。With the increase of blooming information and data transmission of internet, the perspective of fiber-optic communication becomes more and more prospect in the future. In this dissertation, we focus on the use and design of quantum well (QW) and quantum dot (QD) devices to achieve broadband emission characteristics and higher modulation bandwidth of semiconductor laser diodes (LD) and semiconductor optical amplifiers (SOA).
First, we propose a new simple method to measure the broadband gain spectrum with a two-section device. Without any other external tunable lasers and complicated setup, we measured broadband gain spectrum of quantum-dot amplifiers. The quantum dots give positive gain for the spectral range near 480nm, covering from 950nm to 1400nm. The maximum gain could be 42.83cm-1.
Besides, we find out the infrared emission in the second quantized state device. The reason is supposed to be the free electron’s intersubband transition in the conduction band. By the small energy band gap, the emission of the QDs has the infrared wavelength.
In Addition, we propose a new mechanism for direct modulation of laser diode by using second quantized state device. Lasing at the second quantized state can be induced by increasing the total cavity loss, which can be practically accomplished either by decreasing the length of cavity, increasing the material loss, or by decreasing the facet reflectivity. In our experiment, the bandwidth of the QD device lasing at the second quantized state highest could achieve 2.78GHz. Furthermore, it also enhanced the modulation speed over 2.6 times more than the first quantized state. In addition, we also analysis this result using theoretical model. It helps us to figure out the mechanism of the carriers and the photons.
Finally, we continue to measure the direct modulation of laser diode by using carrier redistribution inside nonidentical multiple quantum wells (MQWs). With proper design of the nonidentical MQW structure, a device with two-section waveguide Fabry-Perot laser diodes can be switched between two widely separated lasing wavelengths at high frequency. The switched intensity can have extinction ratio of 20dB within 5mA of current variation. Carriers redistribute inside nonidentical MQWs and contribute to different lasing wavelengths. Because the transport time between quantum wells is much smaller than the diffusion and drift time in SCH layer of carriers, the modulation bandwidth of two-section laser is expected to surpass the relaxation frequency of conventional laser diode. This new mechanism will greatly improve the transmitter speed and lower the cost in optical communication system.第一章 簡介 1
第二章 半導體雷射與光放大器的基本特性量測與分析 7
2-1 簡介 7
2-1-1 奈米結構 7
2-1-2 基本特性的實驗量測之架設 10
2-2 量子井雷射與光放大器特性量測 14
2-2-1 量子井設計原理與元件結構 14
2-2-2 量子井雷射與光放大器的特性量測與分析 21
2-3 量子點雷射與光放大器特性量測 33
2-3-1 量子點設計原理與元件結構 33
2-3-2 量子點雷射與光放大器的特性量測與分析 38
2-4 結論 44
第三章 寬頻量子點半導體光放大器的增益頻譜量測 46
3-1 簡介 47
3-1-1 研究動機 47
3-1-2 使用兩段式元件量測增益頻譜之原理 50
3-2 量子點結構之寬頻半導體光放大器 54
3-2-1 量子點雷射的寬頻特性 54
3-2-2 量子點結構之設計與製作 55
3-3 實驗之架設與量測 60
3-4 實驗結果與討論 62
3-4-1 頻譜量測結果 62
3-4-2 增益頻譜之分析 66
3-5 結論 69
第四章 第二量子化能階之量子點雷射在兆赫輻射源上的應用 70
4-1 簡介 70
4-1-1 發展歷史 71
4-1-2 物理機制 73
4-1-3 兆赫輻射之應用 74
4-2 研究動機 75
4-2-1 量子串接雷射 77
4-2-2 量子點雷射 79
4-3 實驗系統架設 81
4-3-1 元件之固定與溫控 81
4-3-2 傅氏轉換紅外線光譜儀 83
4-4 實驗結果之分析與討論 87
4-5 結論 96
第五章 應用第二量子化能階的量子點雷射來增加調變速度 98
5-1 簡介 99
5-1-1 外部調變 100
5-1-2 直接調變 104
5-1-3 外部調變與直接調變之優缺點比較 106
5-2 量子點結構的設計與特性 108
5-3 實驗架設與量測結果 110
5-4 分析與討論 121
5-4-1 高頻小訊號反射效應 122
5-4-2 RC時間常數效應 127
5-5 理論模擬計算 131
5-5-1 差動增益模型 133
5-5-2 計算結果 137
5-6 結論 139
第六章 應用非對稱多重量子井結構在半導體雷射
的波長轉換與直接調變 143
6-1 簡介 144
6-2 非對稱量子井間載子移動之理論模型 146
6-3 元件之設計與製作 151
6-3-1 非對稱多重量子井結構之設計 151
6-3-2 兩段式直波導元件的製作 155
6-4 直流訊號的波長轉換量測 156
6-5 小訊號的高頻直接調變量測 164
6-6 結論 170
第七章 總結與未來展望 171
7-1 論文回顧 171
7-2 未來展望 176
附錄一 網路分析儀原理 179
參考文獻 18
Population size and stocking contribution rates for marked and recaptured black porgy Acanthopagrus schlegelli, in Northwestern Taiwan, 2005-2008
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