氢分子在磁场中回归谱的散射矩阵理论研究

利用散射矩阵理论，结合扩展的半经典闭合轨道理论和多通道量子亏损理论，计算了磁场中高里德堡H2分子的回归谱．该方法使用了两个空间散射矩阵来描述里德堡电子的动力学性质，计算中可以包括所有阶的实散射的作用．回归谱的每一个尖峰对应着一条闭合轨道，新的额外峰是由于弹性散射和非弹性散射所引起的通道内和通道间的轨道组合，进一步证明了体系通道间和通道内的散射具有同等的重要性．     

氢分子在磁场中回归谱的散射矩阵理论研究

利用散射矩阵理论,结合扩展的半经典闭合轨道理论和多通道量子亏损理论,计算了磁场中高里德堡H2分子的回归谱.该方法使用了两个空间散射矩阵来描述里德堡电子的动力学性质,计算中可以包括所有阶的实散射的作用.回归谱的每一个尖峰对应着一条闭合轨道,新的额外峰是由于弹性散射和非弹性散射所引起的通道内和通道间的轨道组合,进一步证明了体系通道间和通道内的散射具有同等的重要性.     

氢分子在磁场中回归谱的散射矩阵理论研究

利用散射矩阵理论,结合扩展的半经典闭合轨道理论和多通道量子亏损理论,计算了磁场中高里德堡H2分子的回归谱.该方法使用了两个空间散射矩阵来描述里德堡电子的动力学性质,计算中可以包括所有阶的实散射的作用.回归谱的每一个尖峰对应着一条闭合轨道,新的额外峰是由于弹性散射和非弹性散射所引起的通道内和通道间的轨道组合,进一步证明了体系通道间和通道内的散射具有同等的重要性.     

里德堡NO分子在强磁场中的回归谱

利用分子轨道理论,结合一个新的模型势,我们给出了里德堡NO分子中激发态电子所受到的作用势的解析表达式.利用分子的闭合轨道理论和分区自洽的迭代方法,首次从理论上计算了NO分子在强磁场中的回归谱.通过和A.Matzkin等人给出的NO分子在强磁场中的实验谱的比较,表明我们的计算是正确的.     

强磁场中Rydberg NO分子的回归谱研究

利用分子的闭合轨道理论和多通道量子亏损理论,考虑核的转动影响,计算了Rydberg NO分子在外磁场中的回归谱.研究表明,复杂谱的结构可以用包含分子实散射的闭合轨道理论来解释,不管是同一通道内的弹性散射还是不同通道间的非弹性散射都起着非常重要的作用,尤其是较大标度作用量下,散射作用远大于基本轨道和重复轨道的贡献,很大程度上影响着体系的动力学性质。     

外电场中Li原子回归谱的分岔效应

半经典闭合轨道在外场和激光参数的某些值附近发生分岔，导致波函数的发散，使原有的半经典闭合轨道理论失效-计算了高激发的Li原子在标度能量为ε=-2-94，标度电场在135 -86-1/4<160-11范围内光吸收谱的Fourier变换，分析了轨道分岔现 象及其影 响，并采用了一种适用于不同能域的统一近似方法修正了分岔点附近波函数-计算中考虑了 原子实多重散射组合回归效应，并把所得回归谱与用标准半经典闭合轨道理论对Li原子及H 原子的计算结果相比较，证明了轨道分岔效应的重要性- 关键词： 分岔 统一近似 半经典闭合轨道理论 回归谱     

垂直电磁场中He原子的吸收谱和回归谱的理论计算

半经典闭合轨道理论已经成功地计算了在外加磁场和平行电磁场中的里德堡原子的回归谱.但对于垂直电磁场中的里德堡原子,理论和计算都变得更为复杂.本文把闭合轨道理论推广到三维情况,采用 B.Hüpper的模型势计算了ε=-0.03,主量子数n≈ 40,m=0下He原子在垂直电磁场中的光吸收谱和回归谱,并和H原子在垂直电磁场中的回归谱作比较,突出了实散射的贡献.计算中应用了离子实散射的分区自洽迭代方法,并考虑到轨道的多次重复和离子实的多次散射效应.这是对闭合轨道理论的验证和进一步推广.     

Li里得堡原子在振荡场中的回归谱研究

文中应用扩展的半经典闭合轨道理论计算了Li原子在平行电磁场加一个振荡电场中的回归谱.与相同情况下平行电磁场中的回归谱比较,当附加含时振荡场时,静外场中的吸收光谱的强度被很大程度地减弱.另外,分别讨论了回归谱强度随振荡场振幅以及频率的变化规律.     

平行电磁场中He原子回归谱中的排斥势效应

利用包括实散射的闭合轨道理论和分区自洽迭代的计算方法,研究了在标度能量~ε=-0.03和标度电场~f=0.01的情况下He(M=1)原子在平行电磁场中的闭合轨道和光吸收的回归谱.与相同条件下的He(M=0)原子的回归谱相比较,由于z轴处的排斥势,减小了原子实短程衍射效应和电子的关联,使谱变得简单,这与实验的结果一致.     

平行电磁场中He+2的回归谱与闭合轨道的研究

利用半经典闭合轨道理论和分区自洽迭代方法计算了Rydberg态下He⁺₂在平行电磁场中的回归谱与闭合轨道. 为了模拟分子实的散射作用,引入一个包含电子交换势的新势能. 利用这一新势能,结合多通道量子亏损和分子闭合轨道理论,讨论了分子实散射效应对平行电磁场中He⁺₂的回归谱与闭合轨道的影响. 关键词： 回归谱 分子半经典闭合轨道 交换势 实散射     

Short-ranged potential effects on the recurrence spectra of lithium M = 1 atoms in parallel electric and magnetic fields

This paper presents recurrence spectra of highly excited lithium atoms with M = 1 state in parallel electric and magnetic fields at a fixed scaled energy ε = -0.03. Short-ranged potentials including ionic core potential and centrifugal barrier are taken into account. Their effects on the states and photo-absorption spectrum are analysed in detail. This demonstrates that the geometric features of classical orbits are of special importance for modulations of the spectral pattern. Thus the weak polarization as well as the reduction of correlation of electrons induced by short-ranged potentials give rise to the recurrence spectra of lithium M = 1 atoms more compact than that of the M = 0 one, which is in good agreement with the experimental prediction.     

Recurrence spectra of non—hydrogen Rydberg atoms in paralled electric and magnetic fields

We present a new method for computing the recurrence spectra of n≈40, m=0 lithium Rydberg atoms in strong parallel external electric and magnetic fields. This method is based on an extended closed-orbit theory allowing the computation of the scattering of the electron by the ionic core. We pay particular attention to the scaling properties, which are extremely important for understanding the correspondence between classical and quantum mechanics. The spectra with a constant scaled electric field \tilde F=0.01 and a scaled energy ε=-0.03 are recorded and compared with those of hydrogen obtained by the standard closed-orbit theory. The result shows that the additional strong resonance structures can be interpreted in terms of the core-scattered classical closed orbits.     

Semiclassical calculation of Rydberg He2^＋ molecular of recurrence spectra ion in a magnetic field

Making use of the molecular closed-orbit theory and a new model potential for the Rydberg molecule, we have calculated the recurrence spectra of He^2＋ molecular ion in a magnetic field for different quantum defects. The Fourier transform spectra of He^2＋ molecular ion may be used to perform a direct comparison between peaks in the spectra and the scaled action values of closed orbits of the excited electron in external fields. We find that the spectral modulations can be analysed in terms of the scattering of the excited electron on the molecular core. Unlike the case of the Rydberg atom where the elastic scattering is predominant, modulations produced by inelastic scattering are also vital to the photoabsorption spectrum of the Rydberg molecule. Our results are in good agreement with the quantum results, which suggests that our method is correct.     

Scattering matrix theory for Cs Rydberg atoms in magnetic field

Based on the closed orbit theory framework together with the quantum defect theory and time-independent scattering matrices theory, we calculate the recurrence spectra of diamagnetic Cs atoms at several different scaled energies near the second ionization threshold. It is revealed that the new extra peaks in spectra are attributed to the combination recurrences of semiclassical closed orbits arising from core-scattered events. This method considers the dynamic states of the Rydberg electron in the core region and long-range region and can be analytically resumed to include all orders of core-scattering automatically. With this approach a convergent recurrence spectrum can be reasonably achieved. It is found that the spectral complexity depends highly sensitively on the scaled energy. With the increase of the scaled energy, the spectral structure changes from simple to complicate and the dynamic feature from regular to chaotic. The comparison of the recurrence spectra with Dando’s result under the same conditions demonstrates that there exist some similarities and differences between them, and furthermore, the feasibility of the scattering matrix method is explained. Supported by the National Natural Science Foundation of China (Grant Nos. 10774093 and 10374061)