利用色散遞增光纖產生頻譜壓縮雙峰與特性分析

Generation and Analysis of Dual-Peaked Laser Spectral Compression Using a Dispersion-Increasing Fiber

林裕翔(Lin, Yu Hsiang)

指導教授 ： 黃承彬

國立清華大學/電機資訊學院/光電工程研究所/碩士(2014年)

https://doi.org/10.6843/NTHU.2014.00006

摘要

雷射光頻譜壓縮藉由能量在頻譜上的重新分佈，達到增加頻譜亮度，亦即頻譜訊雜比之目的，有助於提升飛秒雷射和超連續光頻譜的應用及發展性。本論文使用線性色散遞增光纖，透過絕熱系統下光孤子脈衝壓縮的反向操作達到頻譜壓縮。
然而，近年來有關頻譜壓縮的研究仍局限於頻譜上存在單一高峰的範疇。本論文成功地利用色散遞增光纖產生頻譜壓縮雙峰，且頻譜雙峰的特性，包括相對振幅及波長得以透過雷射源的平均功率、入射脈衝啁啾的條件調整並做分析。比對以飛秒鎖模脈衝為雷射源所量測到的實驗結果與透過非線性薛丁格方程式的數學模型所計算的數值模擬結果，兩者具有非常好的相似性。

關鍵字

光孤子 ； 頻譜壓縮 ； 非線性效應

並列摘要

Femtosecond lasers and optical supercontinua offer wide optical bandwidths but at the same time suffer from low spectral brightness. One solution is to perform external laser spectral compression. Our approach for spectral compression is using a linear ramp dispersion-increasing fiber (DIF), which is reverse processes of adiabatic soliton temporal compression.
However, to date, laser spectral compressions have been limited in generating a single output spectrally compressed peak. We demonstrate the generation of spectrally compressed spectrum with dual peaks. Moreover, the relative amplitudes and wavelengths of the two spectral peaks are adjustable through the average power, input pulse chirp condition. The experimental results are compared to simulations and are found in excellent agreements.

參考文獻

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