【摘要】 采用脉冲宽度为7 fs,脉冲能量为0.4 mJ的超快强激光脉冲与气体盒子中Ar原子作用获得了高次谐波截止区连续谱,并发现当驱动激光稳定在不同的载波包络相位时,高次谐波的谱结构、谱调制深度和连续谱的带宽都有很大区别。在某些载波包络相位时获得了平滑的连续谱,调制深度小于17%,连续带宽达10 eV,从而支持时域上获得变换极限500 as的单个阿秒脉冲。更多还原

【Abstract】 High-order harmonic continuum in the cutoff region is demonstrated with an argon gas cell driven by(7 fs/0.4 mJ) ultrashort intense laser pulses.It is found that the spectral structure,modulation depth and continuum bandwidth vary greatly when the carrier envelope phase(CEP) of driving laser pulse is stabilized at different value.At some CEP value,a smooth continuous spectrum with modulation depth less than 17% and 10 eV continuum bandwidth is achieved,supporting a transform-limited single 500 as pulse in time domain.更多还原