Rydberg atoms in external electric and magnetic fields have recently emerged as atomic-scale laboratories where the quantum mechanics of classically nonintegrable systems can be studied. In this article we show, using classical canonical perturbation theory, how the intricate nonlinear dynamics of a Rydberg electron in crossed electric and magnetic fields can be described in terms of two coupled asymmetric tops.

• Received 11 September 1992

DOI:https://doi.org/10.1103/PhysRevA.47.3113