Rydberg atoms in parallel magnetic and electric fields. II. Theoretical analysis of the Stark structure of the diamagnetic manifold of hydrogen

Abstract

For pt. I see ibid., vol.21, no.21, p.3473-98 (1988). The semiclassical approach based on the secular perturbation method, primarily introduced by Solov'ev (1982) to study the pure diamagnetism of hydrogen in the weak-field limit, is extended to the case where the atom is subjected to electric and magnetic fields both parallel to the 0z direction. The structure of the manifold of states with principal quantum number n is governed by the existence of an approximate constant of motion and the states can be classified into three groups. The semiclassical Bohr-Sommerfeld quantisation rule allows the energy of the states to be calculated. The main properties of the spectra and their evolution when one of the fields increases are analysed. An original comparison between the structure of the pure diamagnetic n multiplet with azimuthal quantum number M not=0 and the structure of the n, M=0 multiplet with parallel fields is proposed.