Radiative decay of Trojan wave packets

TLDR: In this paper, the decay rate of Trojan wave packets due to spontaneous emission was analyzed and it was shown that this process is much slower than the ionization process, and the concept of Trojan states has been further generalized by adding the magnetic field to achieve an even stronger stabilization of the wave packets.

Abstract: It has been recently shown theoretically @1‐6# that in highly excited atoms placed in a strong, resonant circularly polarized electromagnetic wave there exist dressed electronic states in the form of nonstationary, nonspreading wave packets, called Trojan wave packets @1#. These states are highly stable against ionization @5# with a lifetime of about 10 6 Kepler periods for wave packets corresponding to n560. In the present paper we calculate the decay rate of Trojan wave packets due to spontaneous emission and show that this process is much slower that the ionization. The concept of Trojan states has been further generalized @7‐11# by adding the magnetic field to achieve an even stronger stabilization of the wave packets. However, in the present paper we do not consider the influence of the magnetic field. In order to perform the calculation of the lifetime, we have to generalize the standard method based on the Fermi golden rule, as shown in @12#, to deal with transitions between nonstationary, rotating states. The dynamics of Trojan wave packets interacting with the quantized electromagnetic field is governed by the Hamiltonian