超短脈衝的產生使人們得以窺見大自然中更加快速的動態過程，隨著近年來超快光學的迅速發展，雷射脈衝在時域上的寬度逐漸被推進到埃秒領域（1埃秒等於〖10〗^(-18) 秒），此埃秒光脈衝與激發-偵測技術（pump-probe）的結合為人們打開了探索原子系統中電子動態的大門。目前高次諧波（high-order harmonic generation）是用來產生埃秒光脈衝的主要方法之一，然而利用此方法所產生的埃秒光脈衝伴隨顯著的光色散現象，使的埃秒光脈衝在時域上的寬度遠大於其理想的脈衝寬度（transform-limited pulse duration）。因此準確量測所產生的埃秒光脈衝不僅是為了決定動態實驗中的時間解析能力，也是在發展如何提升時間解析能力時不可或缺的技術。
本篇論文的目的在於量測實驗中所產生的極紫外光埃秒脈衝，此量測技術的核心原理為雷射輔助之光致游離 (laser-dressed photoionization)。因此我們先將極紫外光埃秒脈衝藉由光致游離轉化為複製電子波，在游離電子的過程中同時給予另一干擾雷射電場，改變游離出來的電子動能。我們收集這些電子並量測其動能，就可以得到這個電子波的頻譜。此電子頻譜隨延遲時間改變而有所不同，紀錄不同延遲時間所產生的電子頻譜並依照延遲的時間排列，可以得到光電子時頻譜。我們最後藉由適當的迭代演算法從中分析極紫外光埃秒脈衝的振幅與相位資訊，利用這些資訊我們便可以在時間上重建極紫外光埃秒脈衝的波型並分析其在時間上的脈衝寬度，這是埃秒光源脈衝量測的關鍵技術。

The generation of ultrashort pulses provides an avenue for exploring the fast-evolving phenomena in nature. Since recent advancement in ultrafast optics has pushed the duration of laser pulses from femtosecond to attosecond regime, even electron dynamics in atomic systems can be tracked by pump-probe measurement technique. However, the attosecond pulses produced from high-order harmonic generation (HHG) inherently possess attochirps which affect the pulse duration of generated attosecond pulses. Complete characterization of arbitrary attosecond pulses, therefore, is indispensable not only to determine but also to further increase the temporal resolution for time-resolved measurements.
In this thesis, we characterized the temporal profile of extreme-ultraviolet (EUV) attosecond pulses by using the photoelectron streaking technique where the generated EUV attosecond pulse is converted to its electron replica through photoionization in the presence of a delayed infrared (IR) dressing laser field. After properly adjusting the delay between attosecond pulses and dressing laser fields, a streaked spectrogram of energy as a function of delay can be obtained. By feeding this streaked spectrogram into an iterative algorithm, the temporal information about both EUV attosecond pulses and IR dressing fields can be extracted simultaneously and consequently the temporal profile of these pulses can be fully reconstructed. This measurement technique is essential for attosecond science.

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