The Ryderberg electronic wave packet dynamics of hydrogen atom near helium surface in an electric field is investigated using the semiclassical method. The autocorrelation function is calculated when the photoionized electron is excited by a short laser pulse for different atom-surface separations. The results show that new recurrences appear because of the helium surface, and the number of recurrent peaks increases with the decrease in atom-surface distance. The new feature is ascribed to the bifurcation of new closed orbits in the classical dynamics of the photoionized electron. Therefore, surface properties have a significant effect on the spectrum of nearby atoms or ions.

The autocorrelation function of electronic wave packet of hydrogen atom in a strong electric field below the zero-field ionization threshold is investigated in the formalism of semiclassical theory. It is found that the autocorrelation depends on the applied laser pulse significantly. In the case of narrow laser pulse, the reviving peaks in the autocorrelation can be attributed to the closed orbits of electrons, which are related to the classical dynamics of the system. But this correspondence is wiped out with increasing the laser width because of the interference among the adjacent reviving peaks.