基于阿秒XUV-飞秒IR泵浦-探测的冷靶反冲离子动量成像谱仪

利用多道可见光谱探测系统测量了Hα、CⅢ(464.7nm)和OⅡ(441.5nnm)谱线的时间行为,得出了碳、氢和氧元素的入射通量。在简化模型下算出了氧碳间的化学溅射率,结果表明HT-6M托卡马克边界杂质产生机制主要是氢氧间的化学溅射和氧碳间的化学溅射,因此控制氧杂质尤其重要。     

Phase dependence of third-order harmonic generation in gases induced by two-color laser field

We experimentally demonstrate third-harmonic generation(THG) in gases ionized by a femtosecond laser pulse superimposed on its second-harmonic(SH). The mechanism of THG has been investigated, and it demonstrates that a third-order nonlinear process dominates at low pump intensity. Asymmetric third-harmonic(TH) spectra are observed at different time delays in two color fields, which are attributed to the process of the four-wave mixing(FWM) of the broad spectrum of pump pulses. A joint measuremen...