双色激光脉冲辐照叠加态生成强的38 as孤立脉冲

采用多周期800 nm激光组合1 600 nm红外激光脉冲辐照氦离子He⁺叠加态生成强、短孤立阿秒脉冲. 结果表明,相对于800 nm单色激光辐照基态情形,截止频率由70次谐波大幅度展宽到280次谐波,且获得频宽为108 eV并由单一短量子路径贡献的连续辐射谱,叠加该连续谱210次到280次谐波获得了脉宽为38 as的强、短孤立脉冲,其强度比单色场情形提高了11个数量级. 研究进一步表明,两束激光脉冲的时间延迟从0.05π到－0.05π之间获得的孤立阿秒脉冲是最优化的,且脉冲持续时间 关键词： 组合激光脉冲 相干叠加态 阿秒脉冲

Isolated intense 38 attosecond pulse generation from the combined laser pulse irradiating the coherent superposition state

A scheme to efficiently generate an intense short isolated attosecond pulse is presented by the combined laser pulse irradiating the coherent superposition state.The combined pulse is composed of a multi-cycle 800 nm laser and a 1600 nm one.Compared with the case of the fundamental laser irradiating the ground state,the cutoff position is significantly extended from 70th to 280th harmonic,a broadband supercontinuum spectrum with 108 eV spectral width can be produced which directly generates an isolated 38 a...