Dynamics of a two-electron quantum system in a strong laser field

Dynamics of a one-dimensional negative hydrogen ion H- in a strong laser fi eld is studied. Different approaches (a one-electron model and Hartree and Hartree-Fock approximations) are compared with the exact numerical solution of the two-dimensional time-dependent Schrodinger equation. The probabilit ies of single and double ionization are calculated for various frequencies and intensities of laser radiation. Strong electron-electron correlations a re shown to manifest themselves in the ground state and the dynamics of dou ble ionization in exact two-particle simulations. Stabilization against ion ization is investigated for a two-electron system. Predictions of a one-ele ctron model qualitatively agree with the results of exact two-particle simu lations in the range of intensities corresponding to one-electron ionizatio n. The approximation of self-consistent field does not seem to be reliable even in the case of one-electron ionization.