外电场中Li原子回归谱的分岔效应

A study of the bifurcation effect of closed orbits on the recurrence spectra of Li Rydberg atoms in an external electric field

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 <F- 1 4 <16 0 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 。

The semiclassical closed-orbit theory begins to fail when the returning wave becomes infinite near the core, and this is the typical situation when bifurcations of closed-orbits occur. We describe the phenomena of bifurcations and calculate the recurrence spectra of Li Rydberg atoms in the vicinity of the bifurcation energy using the uniform approximation method. The spectra with a constant energy epsilon = - 2.94, and a constant scaled electric field 135.86 < F-1/4 < 160.11 are recorded and the effect of the core-scattering is taken into account. The recurrence spectra are compared with those obtained by the primary extended closed-orbit theory and those of hydrogen atoms. The results display the important contributions of bifurcations and core-scattering to the recurrence spectra of Li Rydberg atoms.