The Enhancement of Efficiency of High-order Harmonic in Intense Laser Field Based on Asymptotic Boundary Conditions and Symplectic Algorithm
The Enhancement of Efficiency of High-order Harmonic in Intense Laser Field Based on Asymptotic Boundary Conditions and Symplectic Algorithm
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DOI：
10.1007/s10910-005-9042-0
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发表时间：
2006-01
影响因子：
1.7
通讯作者：
Chunli Zhang;Xueshen Liu;Peizhu Ding;Y. Qi
中科院分区：
文献类型：
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作者：
Chunli Zhang;Xueshen Liu;Peizhu Ding;Y. Qi
利用最近提出的激光-原子相互作用的渐近边界条件（ABC），将无限空间中时变Schrödinger方程（TDSE）的初值问题转化为有限空间中的初值和边值问题，然后用对称差商代替二阶偏导数，将TDSE离散为线性正则方程。用辛算法求解正则方程。分别以基态和基态与第一激发态的等重相干叠加为初始条件，计算了束缚态的居群、平均距离的演化和高次谐波的产生。初始相干叠加态和适当的激光强度可以提高HHG的转换效率
Asymptotic boundary condition (ABC) of laser-atom interaction presented recently is applied to transform the initial value problem of the time-dependent Schrödinger equation (TDSE) in infinite space into the initial and boundary value problem in the finite space, and then the TDSE is discretized into linear canonical equations by substituting the symmetry difference quotient for the 2-order partial derivative. The canonical equation is solved by symplectic algorithm. The ground state and the equal weight coherent superposition of the ground state and the first excited state have been taken as the initial conditions, respectively, while we calculate the population of bound states, the evolution of average distance and the high-order harmonic generation (HHG). The conversion efficiency of HHG can be enhanced by initial coherent superposition state and moderate laser intensities