非週期性超精細准相位匹配光學超晶格之研究

Hyperfine aperiodic optical superlattice for quasi phase-matching

賴瑞禹(Jui-Yu Lai)

指導教授 ： 楊尚達

國立清華大學/電機資訊學院/光電工程研究所/碩士(2010年)

摘要

本篇論文利用Sequential search algorithm達成Hyperfine aperiodic optical superlattice (H-AOS)晶體之設計，在不違反製程下限所能達到的區域大小下限之下，將晶格長度的解析度推進到製程能力極限。在晶體長度相同的狀況下，3根等高不等間距匹配尖峰，與5根V型等間距匹配尖峰兩個設計目標，本方法所得之轉換效率超越以往最高的方法達到9%，同時運算時間也大幅縮短十餘倍。另外我們也分別設計：(1) 40個匹配尖峰設計。(2) 1~2.4μm大頻寬範圍之相位匹配尖峰設計。(3)立方函數分佈之相位匹配尖峰群設計。(4)Super Gaussian形狀之連續相位匹配功率頻譜設計。(5)寬頻平坦連續相位匹配功率頻譜設計。(6)無sidelobe之sinc2相位匹配功率頻譜，以證明此方法在設計上的彈性，並以程式隨機計算的方式證明此方法已經極度趨近全域的最佳解。

關鍵字

超精細非週期光學超晶格

並列摘要

In this paper, we report a new method, hyperfine aperiodic optical superlattice (H-AOS) optimized by sequential search algorithm (SS). The domain size of H-AOS remains longer than the minimum domain length dmin (~4.5 m), which can be reliable poled and the resolution is equal to the photolithographic mask (~100nm). H-AOS method enhance the overall efficiency by ~9% and greatly reduce the computation time by a factor of ~15 simultaneously compare to NOS method in 3 PM peaks and 5 PM peaks design. We also demonstrate the (1) 40 PM peaks, (2) 1.15~2.4m wide 4 PM peaks, (3) cubic shape PM peaks, (4) Super gaussian shape continuous PM curve, (5) continuous flat-top PM band, (6) sidelobe suppression for sinc2 PM power spectrum, to show the flexibility of our method. We also use program to show that the design by H-AOS is very closed to the global maximum.

並列關鍵字

Hyperfine aperiodic optical superlattice

參考文獻

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