Harmonic generation in a 1D model of H2 with single and double ionization

Single and double electron ionization probabilities are calculated numerically for the first three electronic states of a 1D model of H-2 in an ultrashort (t < 10 fs) intense (I >= 10(14) W cm(-2)) longwavelength (lambda = 800 nm) laser pulse. High order harmonic generation spectra are also presented in intensity regimes where single and double ionizations dominate. Numerical results are presented at equilibrium. and of the critical internuclear distance R, where charge resonance enhanced ionization, CREI, occurs. Comparison of the harmonic generation plateaus at different intensities and. the two different internucleai distances allows for an evaluation of the influence of electron correlation and symmetry of the two-electron wavefunction.