排序方式: 共有23条查询结果,搜索用时 31 毫秒
1.
Terahertz(THz) wave emission from argon atom in a two-color laser pulses is studied numerically by solving the one-dimensional(1D) time-dependent Schr ¨odinger equation. The THz spectra we obtained include both discontinuous and continuum ones. By using the special basis functions that we previously proposed, our analysis points out that the discontinuous and continuum parts are contributed by bound–bound and continuum–continuum transition of atomic energy levels. Although the atomic wave function is strongly dressed during the interaction with laser fields, our identification for the discontinuous part of the THz wave shows that the transition between highly excited bound states can still be well described by the field-free basis function in the tunneling ionization regime. 相似文献
2.
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
3.
引入非线性空间变换,用伪谱方法求解了一维原子在强激光场中的薛定谔方程,再利用B样条函数和傅立叶级数的线性组合构造原子未微扰的本征函数,计算了一维原子在强激光场中的阈上电离谱,其结果与分裂算符法得到的结果符合得很好. 相似文献
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
5.
We study the ionization probabilities of atoms by a short laser pulse with three different theoretical methods,i.e.,the numerical solution of the time-dependent Schro¨dinger equation(TDSE),the Perelomov-Popov-Terent’ev(PPT) theory,and the Ammosov-Delone-Krainov(ADK) theory.Our results show that laser intensity dependent ionization probabilities of several atoms(i.e.,H,He,and Ne) obtained from the PPT theory accord quite well with the TDSE results both in the multiphoton and tunneling ionization regimes,while the ADK results fit well to the TDSE data only in the tunneling ionization regime.Our calculations also show that laser intensity dependent ionization probabilities of a H atom at three different laser wavelengths of 600 nm,800 nm,and 1200 nm obtained from the PPT theory are also in good agreement with those from the TDSE,while the ADK theory fails to give the wavelength dependence of ionization probability.Only when the laser wavelength is long enough,will the results of ADK be close to those of TDSE. 相似文献
6.
We investigate theoretically the ionization properties of the valence electron for the alkali metal atom Na in an intense pulsed laser field by solving numerically the time-dependent Schr ¨odinger equation with an accurate l-dependent model potential.By calculating the variations of the ionization probabilities with laser peak intensity for wavelengths ranging from 200 nm to 600 nm,our results present a dynamic stabilization trend for the Na atom initially in its ground state(3 s) and the excited states(3 p and 4 s) exposed to an intense pulsed laser field.Especially a clear "window" of dynamic stabilization at lower laser intensities and longer wavelengths for the initial state 4 s(the second excited state) is found.By analyzing the time-dependent population distributions of the valence electron in the bound states with the different values of principal quantum number n and orbital quantum number l,we can attribute the dynamic stabilization to the periodic population in the low-excited states since the valence electron oscillates rapidly between the lowly excited states and the continuum states. 相似文献
7.
利用R矩阵方法计算了电子与He+离子碰撞的1s-2s和1s-2p跃迁的碰撞强度,结果表明包括10个靶态的计算可以得到精确的类氢离子的n=1→n=2各能级跃迁的碰撞强度,并首次利用R矩阵方法计算了电子与Li2+离子碰撞的1s-2s和1s-2p跃迁的碰撞强度. 相似文献
8.
9.
10.
Two-dimensional (2D) electron momentum distributions and energy spectra of a hydrogen in an intense laser field are calculated by solving the time-dependent Schrödinger equation combined with the window-operator technique. Compared with the standard projection technique, the window-operator technique has the advantage that the continuum states of atoms can be avoided in the calculation. We show that the 2D electron momentum distributions and the energy spectra from those two techniques accord quite well with each other if an appropriate energy width is used in the window operator. 相似文献