近十年來飛秒 (fs, 10-15 sec) 雷射科技的快速進展，已使其成為許多研究領 域所不可或缺的工具，它不僅成為尖端非線性光學以及時間解析光譜學的基礎， 在許多新的領域更有令人驚異的應用， 例如光孤子通訊 (soliton communication) 、兆赫波光電子學 (terahertz-wave optoelectronics) 、微結構製造 (microstructure fabrication)、多光子顯微術 (multi-photon microscopy) 等等。最近 飛秒雷射更是被發展作為精確頻率尺 (frequency rulers)，用來校正最精確的原子 躍遷。超短時寬脈衝雷射振盪器的建造有三個關鍵要素。第一是寬頻的雷射增益 介質(gain medium)，第二是適當的脈衝壓縮機制，第三是精確的色散補償，三者 兼備方能達成超短雷射脈衝的產生。 本文利用光學薄膜設計一種干涉式啁啾共振腔色散補償濾光片 (chirped-cavity dispersion compensator filter ， CCDCF) ， 設計中結合了 Gires-Tournois 干涉濾光片及啁啾(chirped)濾光片的優勢，使其具有更彈性的頻寬 及群速度延遲色散值。此啁啾共振腔色散補償濾光片以高折射率或低折射率整數 倍的二分之ㄧ波膜厚為空間層，並以啁啾結構之反射鏡為兩側之高反射鏡為其基 本結構。在本論文中所設計之啁啾共振腔色散補償濾光片提供了-50 fs2 之群色散 值，頻寬達56THz，而其膜堆之光學厚度僅為Gires-Tournois 干涉濾光片及啁啾 濾光片之一半。論文中並架設一光纖式馬赫任德(Mach-Zehnder)干涉儀量測干涉式濾波片之群延遲(group delay)。此干涉儀提供一簡單、精確且可物理性地瞄繪 出一光學脈波在一般光學材料內拓寬之行為。文中並以量測100GHz 之高密度多 波分工濾波片為例，說明量測時間之長短及高斯視窗之選擇為此量測方式可行的 兩大重點。The fast progress of femto-second (fs, 10-15 sec) laser technology in the past ten years, has already made it become a lot of tools with indispensable research field, it not merely becomes the most advanced nonlinear optics and time foundation of analyzing spectroscopy, have amazing application even more in a lot of new fields, such as soliton communication, terahertz-wave optoelectronics, microstructure fabrication and multi-photon microscopy etc.. Recently, the development of femto-second laser is regarded as accurate frequency rulers which can be used for correcting the transition of photonics accurately. There are three key elements to exceed the construction of the ultra-short pulse laser oscillator. First is the gain medium with wide bandwidth, the second is that the proper mechanism of pulse compression, and the third is the accurate chromatic dispersion compensation. Combinating those three key elements combine can yield the ultra-short pulse laser. A new basic structure of dispersive compensation filter, chirped-cavity dispersive compensator (CCDC) filter was designed to include the advantages of small reflectance and group delay dispersion (GDD) ripples and high dispersive compensation like the Gires-Tournois interferometer (GTI) filter and wide working bandwidth like chirped mirror (CM). The structure of CCDC is a cavity-type of Fabry-Perot filter with spacer layer, 2mH or 2mL and chirped high reflector. The CCDC filter can provide a negative GDD of -50 fs2 over bandwidth of 56THz with half optical thickness of the CM or GTI. This study also proposes a Mach-Zehnder interferometer based on the direct group delay measurement of an optical thin film filter. The interferometer provides a simple, accurate and physically intuitive picture of what happens to broadband optical pulses on common optical materials. A 100GHz DWDM filter was used as an example in the measurement and showed that the time of measurement and selection of Gaussian window were two important factors.
