https://doi.org/10.1140/epjd/e2003-00007-y
The Rydberg atom in collinear static and harmonic electric fields
1
V.A. Fock Institute of Physics,
The University of St Petersburg,
198904 St Petersburg, Russia
2
Institute of Physics and Astronomy,
Aarhus University, 8000 Aarhus C, Denmark
Corresponding authors: a Valentin.Ostrovsky@pobox.spbu.ru - b horsdal@ifa.au.dk
Received:
2
May
2002
Revised:
23
September
2002
Published online:
21
January
2003
In Rydberg atoms subject to static and harmonic collinear electric fields, intrashell transition can be induced by the first order perturbation from a small perpendicular electric or magnetic field, or by effects of the second order in the major fields. Both mechanisms lead to resonances that are suppressed under certain conditions, and high-frequency interference oscillations in case of non-adiabatic field switching. Recent measurements of microwave ionization signals show very rich and fascinating structures similar to the ones predicted for intrashell mixing. We show that the observed ionization structures may be explained by diabatic electric-field ionization and the consistent use of perturbation theory for intrashell mixing. In particular, the dominant oscillation frequency is successfully interpreted in terms of interference between first and second order transition amplitudes. New predictions are provided. The present approach gives a comprehensive picture of intrashell transitions, which may be tested in future experiments designed to observe such transitions directly.
PACS: 32.80.Rm – Multiphoton ionization and excitation to highly excited states (e.g. Rydberg states) / 42.50.Hz – Strong-field excitation of optical transitions in quantum systems; multiphoton processes; dynamic Stark shift
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2003