摘要
本文提出了一个在双色激光场上叠加低频电场来拓宽高次谐波谱平台区域,从而获得孤立40阿秒脉冲的方案.计算中,我们针对氯原子数值求解了一维含时薛定谔方程,并结合电子的经典回碰动能随时间分布图以及时频分析图,分析了低频电场对高次谐波谱产生过程的影响.计算结果表明,该方案可以有效的拓宽谐波谱的平台区域.通过叠加适当阶数的谐波谱,我们得到了孤立40阿秒脉冲.
In this paper, we propose a method to expand the plateau of high-order harmonic spectrum by using the combination of a two-color laser pulse and a low-frequency field, and an isolated 40as pulse is obtained finally. We numerically solve time-dependent Schr＆ouml;dinger equation for the one-dimensional model of helium atom in an intense laser field, analyzing the influence of low-frequency field on high-order harmonic generation （HHG） with classical returning kinetic-energy map and time-frequency distribution. Results show thatnot only is the plateau of harmonic spectrum extended efficiently, but also can the 40as extremely short pulse be obtained by superposing a properly selected range of the harmonic spectrum region.
出处
《原子与分子物理学报》
CAS
CSCD
北大核心
2012年第4期650-654,共5页
Journal of Atomic and Molecular Physics
基金
国家自然科学基金(11047191)
教育部科技研究重点项目(211025)
教育部高等学校博士学科点专项科研基金(新教师类)(20111404120004)
山西省青年科技研究基金(2009021005)
关键词
高次谐波谱
阿秒脉冲
低频电场
平台区域
High-order harmonic spectrum
Attosecond pulse
Low-frequency field
Plateau
