利用高功率超連續光譜產生中心波長不同於種子光源的高功率脈衝雷射

Generation of high-power ultrashort laser pulses from high-power and ultra-broadband supercontinuum

張冠元(Kuan-Yuan Chang)

指導教授 ： 劉佳明

國立交通大學/光電學院/光電系統研究所/碩士(2018年)

摘要

本次實驗利用中心波長為1.56 μm的脈衝雷射產生高功率且寬頻的超續連光譜。產生超連續光譜後，為使系統仍保持全光纖式，我們使用了截止波長分別為780 nm及630 nm的單模光纖作為短通濾波器，並成功產生中心波長約為1.06 μm的脈衝雷射。接著再以摻鐿光纖放大器將所得之1.06 μm脈衝雷射進行功率放大，產生一高功率、脈衝寬度極短的工業用波長脈衝雷射。本次實驗亦同時比較典型脈衝與類噪脈衝的效果差異，兩者皆可達到6 W的輸出功率以及大約11 ps的脈衝寬度。並且發現類噪脈衝即便經過多種放大及非線性機制後，仍然保持其類躁特性。

關鍵字

超連續光譜 ； 脈衝雷射

並列摘要

In this study, we use supercontinuum to generate a high-power and ultrafast laser that has a center wavelength near 1.06 μm, which is different from that of the seed laser at 1.56 μm. To keep the system all-fiber, we use single-mode fibers of different cutoff wavelengths to construct a shortpass filter, instead of the commonly used reflective or transmissive filters in free space. As a result, laser pulses that have a center wavelength near 1.06 μm are filtered through. Then, we use a ytterbium-doped fiber amplifier to amplify the filtered pulses, scaling their average power up to watt-level. Through this approach, high-power, ultrashort laser pulses of respective center wavelengths at 1.56 μm and 1.06 μm that have wide industrial applications can be generated in one system. We also compare the results of noise-like pulses and well-defined pulses: Both kinds of pulses can reach 6 W of maximal average output power, having pulse widths about 11 ps. We find that the noise-like pulses maintain their temporal features better than the well-defined pulses through the processes of amplification, supercontinuum generation, filtering, and further amplification.

並列關鍵字

supercontinuum ； laser pulse

參考文獻

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