摘要
利用分裂算符方法数值求解一维氦原子的含时薛定谔方程,研究了氦原子在两束同色激光场与半周期脉冲(Hcps)形成的组合场驱动下所发射高次谐波的特点.研究结果表明,氦原子在这种组合场驱动下,高次谐波谱的平台区域能得到很大的扩展,其截止位置可延伸到IP+9.6UP,通过构造截止位置附近的高次谐波谱能够得到脉宽为63as的单个阿秒脉冲.经过分析后发现,半周期脉冲的加入不仅使高次谐波谱平台能够得到扩展,同时还抑制了电子长路径对高次谐波的贡献.
By solving numerically the time-dependent Schrdinger equation with the split-operator method,we investigate the characteristic of the high-order harmonic of one-dimensional helium atom exposed to two laser pulses with the same color and half cycle pulses.It is shown that the harmonic spectrum is extended to Ip ＋ 9.6Up in the case of the combined fields,and an isolated 63 as pulse can be obtained by superposing the high-order harmonic spectra generated around the cut-off position.An analysis shows that the plateau of the high-order harmonic spectrum is extended greatly and the contribution of the long electron trajectory is suppressed by adding the half cycle pulses.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2011年第4期165-170,共6页
Acta Physica Sinica
基金
国家自然科学基金(批准号:11044007,11047016)
高等学校博士学科点专项科研基金(批准号:20096203110001)
西北师范大学创新项目(批准号:NWNU-KJCXGC-03-62)资助的课题~~
关键词
两束同色激光场
半周期脉冲
高次谐波
阿秒脉冲
two laser pulses with the same color
half cycle pulses
high-order harmonic
attosecond pulse
