垂直电磁场中He原子的吸收谱和回归谱的理论计算

Semiclassical calculation of the absorption and recurrence spectra of He atom in perpendicular electric and magnetic fields

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.H櫣pper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。

Semiclassical closed orbit theory (COT) has been successfully used to interpret the recurrence spectra of Redberg atom in pure magnetic and parallel magnetic and electric field. But for Redberg atom having multi-electrons in perpendicular magnetic and electric field, the theory is more complicated. In this paper, we extend the closed orbit theory from two degrees of freedom to three non-separable degrees of freedom with special emphasis on core effects. Therefore, we introduce a model potential, calculate absorption spectra and recurrence spectra of He atom in perpendicular magnetic and electric field by using region-splitting consistent and iterative method at ε=-0.03, n≈40,m=0. We also have compared the results with that of hydrogenic atom. Our calculations certify the validity of the closed orbits theory and make some improvement upon it.