通过控制量子路径得到孤立46阿秒脉冲

本篇文章提出了一种利用合成场的方案来获得孤立46阿秒脉冲.首先通过在双色场上叠加低频场得到合成场,其次,我们针对氦原子数值求解了一维含时薛定谔方程.计算结果表明,该方案不仅可以拓宽高次谐波谱的平台区域,也可以有效的选择短量子路径来贡献谐波谱.此外,通过调节低频场的强度可以进一步拓宽谐波谱的平台区域,通过叠加135阶到185阶谐波,可以得到孤立的46阿秒脉冲.

Generation of isolated 46 attosecond pulse via controlling quantum paths

An efficient method to generate an isolated 46-as pulse by using the synthesized laser field is presented. Firstly, the laser field is synthesized by a two-color laser field and a low-frequency field. Secondly, we numerically solve one-dimensional time-dependent Schrödinger equation of helium atom. The results show that not only the width of the plateau can be expanded, but also the short quantum is selected to efficiently contribute to the harmonics. Furthermore, the supercontinuum can be further broadened by adjusting the intensity of the low-frequency field. And by superposing a properly selected range from the 135th to 185th order in the continuous region, an isolated attosecond pulse with a duration of 46-as is obtained.