Abstract

In the group of Delos^1,2 a semiclassical theory has been developed to explain the oscillations observed in the near-threshold absorption spectrum of hydrogenlike atoms in external fields. This theory gives good insight into the physics of the problem and is part of the motivation for the experimental work presented in this contribution. The theory is based on classically closed electron orbits. Each closed orbit contributes an oscillation to the oscillator strength distribution with a frequency related to the period of the orbit. As the electric field Hamiltonian is separable in semiparabolic coordinates in contradistinction to the magnetic field case, all closed orbits remain regular.

© 1994 IEEE