我們採用一個新穎的技術multiple plate continuum(MPC)來產生一個高強度又穩定接近一個單週期脈衝. 這種方法是策略性將多個固態介質薄片晶體擺放在高能量雷射的焦點或接近焦點的位置, 而每個片子的厚度都使得光脈衝在離開薄片前不會產生一些不期望出現的效應而破壞掉脈衝的特性. 這也是第一次成功地在全固態系統中壓縮毫焦耳等級的超寬頻脈衝. 實驗中產生的八度音頻譜在-20 dB的強度水平下覆蓋範圍從420奈米到980奈米, 同時將輸入脈衝能量的64%轉換到超寬頻頻譜中. 之後我們利用由一對光柵和空間液晶調制器組成的壓縮相位系統來補償高階相位色散和細微調整殘留下來的頻率相位以成功製造2.8飛秒的單週期脈衝. 我們同時設計與使用客製化的啁啾鏡來提升我們單週期脈衝的轉換效率. 最後我們成功地利用壓縮好的脈衝應用在高階諧波產生高光子能量的連續頻譜這不僅僅是再一次的證明MPC產生的壓縮脈衝已經在數個週期脈衝區間, 也是一個能夠產生單發埃秒脈衝的應用方式.

Intense and stable near single-cycle pulses are generated by our novel technique of the multiple plate continuum (MPC). This is achieved by strategically placing several thin solid plates at or near the focused waist of a high-power laser pulse. The thickness of each plate is such that the optical pulse exits the plate before undesirable effects begin to take hold of the pulse. This is the first demonstration of mJ-level supercontinuum synthesis in an all solid-state system. The generated octave-spanning spectra that cover from 420nm to 980 nm at the -20 dB intensity level while converting as much as 64 % of the input pulse energy to the supercontinuum. A shaper-assisted 4-f phase compensator consisting of a grating pair and a spatial light modulator (SLM, JenOptik SLM640d) is used to offset the higher-order dispersions and fine-tune the residual spectral phases to produce single-cycle pulses with pulse duration of 2.8 fs. We increased the output efficiency of the near one-cycle pulse by implementing custom-designed chirped mirrors. The continuous spectrum obtained by high-order harmonic (HHG) generation with the compressed pulses serves not only as a second evidence to identify that our pulses are in few-cycle region but also as a good application for the production of an isolated attosecond pulse.

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