Effect of laser pulse shapes on the stabilization of a model atom

Abstract

An atom interacting with a high-frequency, intense laser pulse can be relatively stable against ionization. We investigate this stabilization phenomenon by solving the time-dependent Schrödinger equation numerically for a one-dimensional model atom interacting with a short, intense laser pulse. In particular, we focus our attention on the role of the laser pulse shape by considering different laser pulse envelopes and intensities. We also investigate the role of the range of the potential on the stabilization of the atom as well as the influence of the classical electron displacement at the end of the pulse. We compare a strong-field approximation and a high-frequency approximation with the numerical solution of the time-dependent Schrödinger equation. The strong-field approximation describes well the evolution of the atom only for very short laser pulses. For longer pulses, the high-frequency approximation gives, overall, results which are in good agreement with the numerical solution of the time-dependent Schrödinger equation. We discuss a simple physical picture of the laser-atom dynamics in the intense, high-frequency, short-pulse regime.