如要產生接近原秒範圍的脈衝，則靠近UV的短波長連續頻譜將變得不可或缺。因固體的色散效應較強與較低的損壞閾值，過往實驗都是利用氣體展頻達到此目標，例如使用Ti:sapphire雷射聚焦於充滿惰性氣體的中空波導，產生光束絲和四波混頻。最近本實驗室發現利用幾片晶體產生連續反應，即可產生不錯的展頻成果，此論文即利用此方法在近UV光波段處產生連續頻譜。
內文將先對現今常用的展頻實驗做個回顧，並稍微提到本實驗參考的展頻架構，接著簡介實驗中會用到的理論。因本實驗為利用BBO產生的二倍頻做為展頻光源，而光源能量影響著展頻效果，因此二倍頻的轉換效率理論將會是除了展頻機制的另一重點。實驗部分將分為二倍頻轉換、展頻實驗、脈衝壓縮模擬三部分架構分別介紹，而實驗結果的量測分析與未來計畫則呈現在第四章節。
目前實驗結果為可將原395 nm的脈衝光利用多片晶體展頻至320~480 nm，轉換極限約4 fs的連續頻譜。比起過去研究，本實驗的精小、簡單以及高能量容忍度將會引發大家對於固體在UV部分展頻的新興趣。

Production of single-cycle to subcycle optical transients in the attosecond regime requires coherent pulses that have a continuous spectrum covering the blue to uv region. Such blue to uv pulses have been generated through filamentation and four-wave mixing by focusing intense 800 nm pulses from Ti:sapphire lasers in inert gases confined in hollow waveguides. The use of solid material for the same purpose was not attractive because of large dispersion and low damage threshold. Recently we demonstrated that a similarly broad and intense visible continuum can be generated by strategically placing several thin fused silica plates at or near the focus of the laser beam.
In this thesis we provide first a review of papers that describe the generation of coherent broadband spectrum over the past few years. Then we introduce the basic principle of the generation scheme used in experiment. Because broadband spectrum generation in our scheme is affected by the power of the 395 nm light, the second harmonic generation (SHG) conversion efficiency is of importance in this thesis and is included in the description. The experimental results of SHG, broadband generation, and pulse compression are then described. Analysis of the results and a brief future plan is shown in the final chapter.
So far, we generated a spectrum with a bandwidth covering 320 nm to 480 nm using multiple plates of fused silica. This spectral width can support a transform limited 4 fs. The smaller, simpler setup and higher damage threshold will trigger new interest in the use of bulk material for supercontinuum generation in the uv.

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