共查询到18条相似文献,搜索用时 956 毫秒
1.
用伪谱方法研究强激光场中一维原子的稳定性 总被引:1,自引:1,他引:0
将伪谱方法推广应用到Kramers-Henneberger (KH) 坐标系中求解了一维原子在强激光场中的薛定谔方程,研究了强激光场中一维原子的稳定性.结果表明,在中等强度的激光场中,原子没有发生电离抑制,而在高频超强激光场中,原子的电离受到抑制. 相似文献
2.
3.
4.
利用数值求解原子在强激光场中的含时薛定谔方程,对一维氦原子处于两色红外组合场中产生的高次谐波进行了研究,研究发现,在组合场驱动下,谐波谱的截止位置可以拓展到 ,从而得到脉宽较短的多个阿秒脉冲,通过改变两束激光的相位延迟,最终得到了33.8as的单个脉冲。进一步利用小波变换分析了阿秒脉冲的发射特征,发现单个阿秒脉冲实现是对电子长路径抑制的结果. 相似文献
5.
利用数值求解原子在强激光场中的含时薛定谔方程,对一维氦原子处于两色红外组合场中产生的高次谐波进行了研究,研究发现,在组合场驱动下,谐波谱的截止位置可以拓展到Ip+5.7Up,从而得到脉宽较短的多个阿秒脉冲,通过改变两束激光的相位延迟,最终得到了33.8as的单个脉冲.进一步利用小波变换分析了阿秒脉冲的发射特征,发现单个阿秒脉冲实现是对电子长路径抑制的结果. 相似文献
6.
本文主要介绍量子系统保结构计算最新进展情况,分以下几部分内容:哈密顿系统的辛算法、适合于量子系统的哈密顿量显含时间的辛算法、A2B模型分子和双原子分子系统的经典轨迹辛算法计算、双原子分子CO在激光场中的经典轨迹的辛算法计算及其振动和解离、定态Schr dinger方程的辛形式及求解定态Schr dinger方程本征值问题的辛 打靶法、含时Schr dinger方程的保结构算法及其在激光原子物理中的应用、伪分立态模型、强激光与原子相互作用的渐近边界条件、"非齐线性正则方程"的辛算法及其在计算强激光场中一维原子的多光子电离和高次谐波发射中的应用以及Heisenberg方程的保结构计算等等。 相似文献
7.
量子系统保结构计算新进展 总被引:7,自引:0,他引:7
本文主要介绍量子系统保结构计算最新进展情况,分以下几部分内容:哈密顿系统的辛算法、适合于量子系统的哈密顿量显含时间的辛算法、A2B模型分子和双原子分子系统的经典轨迹辛算法计算、双原子分子CO在激光场中的经典轨迹的辛算法计算及其振动和解离、定态Schr dinger方程的辛形式及求解定态Schr dinger方程本征值问题的辛 打靶法、含时Schr dinger方程的保结构算法及其在激光原子物理中的应用、伪分立态模型、强激光与原子相互作用的渐近边界条件、"非齐线性正则方程"的辛算法及其在计算强激光场中一维原子的多光子电离和高次谐波发射中的应用以及Heisenberg方程的保结构计算等等。 相似文献
8.
强激光与一维多原子分子离子的相互作用及高次谐波的增强 总被引:1,自引:1,他引:0
研究强激光脉冲与一维多原子分子离子的相互作用,讨论双色激光场中高次谐波转化效率的提高,并应用经典三步模型说明高次谐波平台展宽的物理机制. 相似文献
9.
10.
11.
用谱拟合法计算强激光场中氢原子的高次谐波谱 总被引:4,自引:0,他引:4
介绍了一种新的求解含时薛定谔方程的谱拟合法 .该方法把含时波函数在少量且分布稀疏的网格点上拟合 ,结合泰勒级数展开 ,用相对简单的计算得到包括Δt高次项贡献的含时波函数 .并将这一方法用于强激光场中氢原子高次谐波谱的计算 ,得到了与其它方法一致的结果. A new spectral fitting method for solving the time-dependent Schrdinger equation has been developed and applied to the atom in intense laser fields. By using this method, the time-dependent wave functions are determined with few and far between discrete mesh points. And the high accuracy wave functions with contribution of high-order-term of Δt are obtained by using Taylor series expand method. Our method is proved by computing high order harmonic generation spectra of hydrogen in laser fields... 相似文献
12.
13.
利用数值方法求解一维模型氢原子和类氢离子在强激光场中的含时薛定谔方程,研究了由它们产生的高次谐波谱构造的阿秒脉冲规律。研究结果表明,对于高电荷离子而言,由于高次谐波平台的显著展宽,使得构造的相应阿秒脉冲的宽度大幅度缩短,从而可以得到脉宽低于 阿秒的超短脉冲。 相似文献
14.
We theoretically study the high-order harmonic generation (HHG) from a hydrogen atom in an intense few-cycle chirped fundamental laser in combination with an ultraviolet (uv) controlling pulse.The high-order harmonic spectrum is calculated by solving the time-dependent Schr¨odinger equation using the split-operator method.In our calculation,we present the difference of the high-order harmonic spectrum from one-dimensional (1D) model hydrogen atom and three-dimensional (3D) real hydrogen atom.We found that the plateau of the high-order harmonic generation from the 1D case and 3D case are all extended effectively to I p + 35U p due to the presence of the chirped laser pulse and the HHG supercontinuum spectrum is generated by adding an ultraviolet controlling pulse at a proper time,but the efficiency of the HHG for 3D case is more higher at the near cut-off region than the 1D case.Therefore,the generation of the attosecond pulse by synthesizing the harmonics near cut-off region have some slight differences between 1D and 3D simulations.As a real 3D case study,we show that an isolated 18 as pulse with a bandwidth of 232.5 eV is generated directly by optmizing the combination laser fields. 相似文献
15.
通过Crank Nicolson方法数值求解一维氦原子的含时Schrdinger方程,研究了啁啾激光与中红外激光形成组合场驱动氦原子发射高次谐波的特点.研究结果表明,在组合场驱动下,高次谐波平台区能得到很大的扩展,其截至位置得到大幅度扩展,对平台区不同阶次范围的高次谐波进行叠加均能得到单个的阿秒脉冲,最短可实现46 as的单个脉冲输出,经分析发现,中红外场的加入,不仅使高次谐波的平台得到扩展,而且提高了平台区前端的谐波强度.通过经典计算和对电离几率特点的讨论,解释了发生这种现象的原因. 相似文献
16.
High-order harmonic generation spectrum of an excited one-dimensional Coulomb atom in an intense laser field 下载免费PDF全文
Response of the wave packet of a one-dimensional Coulomb atom
to an intense laser field is calculated using the symmetrized
split operator fast Fourier method. The high-order harmonic
generation (HHG) of the initial state separately being the ground and excited states
is presented. When the hardness parameter \alpha in the soft
Coulomb potential V(x)=-1/\sqrt{x^2+\alpha} is chosen to be small
enough, the so-called hard Coulomb potential
V(x)=-1/|x| can be obtained. It is well known that the hard one-dimensional Coulomb atom
has an unstable ground
state with an energy eigenvalue of $\sim0.5$ and it
has no states corresponding to physical states in the true atoms, and
has the first and second excited states being degenerate. The parity effects on the HHG
can be seen from the first and second excited states of the hard
one-dimensional Coulomb atom. The HHG spectra of the excited states
from both the soft and hard Coulomb atom models are shown to have more
complex structures and to be much stronger than the corresponding
HHG spectrum of the ground state of the soft Coulomb model with
$\alpha=2$ in the same laser field. Laser-induced non-resonant
one-photon emission is also observed. 相似文献
17.
18.
A. D. Kondorskii L. P. Presnyakov 《Journal of Experimental and Theoretical Physics》1999,88(4):658-665
The tight-binding method is used to analyze the ionization of a hydrogenlike atom by an intense monochromatic laser field. The orthogonal and normalized basis in which the solution of the time-dependent Schrödinger equation is expanded contains unperturbed wave functions of the discrete spectrum and generalized Coulomb wave functions of the continuum. In the solution of the coupled equations we make use of the fact that the bound-free and free-free transitions are efficient in different regions of complex time. Simplified equations are constructed and investigated. Results of calculations for ionization of a hydrogen atom from its ground state and of the energy distribution of the electrons in strong and superstrong linearly polarized fields are presented. It is shown that in this case the ground state decays completely, and free-free transitions play a defining role in the dynamics of the process. It is established that the total probability of population of the upper Rydberg states abutting the continuum does not exceed 0.05. The range of applicability of the approach is discussed. A comparison with numerical results obtained by other authors is given. 相似文献