非同步諧波鎖模摻鉺光纖雷射重複率提升至40GHz之研究

Abstract

在本論文中，我們成功地將非同步諧波鎖模摻鉺光纖雷射的重複率提升至40GHz，此光纖雷射的數值模型及數值模擬也被演示，在不同重複率下的非同步狀態存在區域、脈衝寬度、光譜頻寬和時間帶寬積的理論預測趨勢與實驗結果相符。在40GHz重複率下，我們進一步探討非同步狀態存在區域在不同調變深度下的變化趨勢，同時藉由使用反饋控制系統，我們能夠僅利用低頻電子儀器將偏差頻率和重複率的變化控制在2kHz的範圍內，這使得對雷射長期穩定所需要的成本可以降低。

In this thesis, we successfully scale an asynchronous harmonic mode-locked Er-doped fiber laser up to 40 GHz repetition rate. The numerical modeling and simulation for the present fiber laser are also demonstrated. The theoretically predicted tendencies of the existence region of the asynchronous state as well as the pulsewidth, optical bandwidth and time-bandwidth product under different repetition rates agree well with the experimental results. At 40 GHz, we further investigate the trend of the existence region of the asynchronous state under different modulation depths. By using the feedback control system, we are able to control the variations of the deviation frequency and the repetition rate within 2 kHz range by utilizing only low frequency electronics, which reduces the cost for long-term laser stabilization.