DYNAMICS OF HYDROGENIC WAVE-PACKETS IN ELECTRIC AND MAGNETIC-FIELDS

The survival probability P(t) of hydrogenic wave packets for some choi ces of strong external electric and magnetic fields is studied. The re cursive residue generation method, in combination with complex dilatio n and a Laguerre basis, is used to calculate the local density of stat es from which P(t) is computed via a Fourier transform. P(t) is calcul ated both for a single initial \8p0> state and for an initial radial h ydrogenic wave packet centered around n=15. In the first case only, in principle, a single n manifold is involved in the dynamics, while in the latter case several n manifolds contribute. The different choices of initial states lead to significantly different results. The choice of fields was made in order to exemplify various patterns of behavior. Results similar to those obtained here were found in recent experimen ts by Broers and co-workers [Phys. Rev. Lett. 71, 344 (1993); Phys. Re v, A 49, 2498 (1994)]. The results presented in this work are quantum- mechanical calculations of hydrogenic wave packets in strong fields th at include the effect of finite lifetimes on P(t).