MOLECULES IN STRONG LASER FIELDS - VIBRATIONAL INVERSION AND HARMONIC-GENERATION

We examine two consequences of the unique behaviour of molecules in strong fields. First, by time gating of laser-induced avoided crossings with femtosecond laser pulses, one can obtain efficient vibrational inversion into a narrow distribution of vibrational levels of a molecular ion. We demonstrate this by numerical solution of the time-dependent Schrodinger equation for H-2(+). Second, we show results of numerical calculation with vibrationally excited H-2(+) of harmonic generation up to the 11th order of an intense 1064-nm laser. We predict that competition of photodissociation can be minimized by trapping the molecule in high-field-induced potential wells, thus enhancing the high-order harmonic generation process. Furthermore, the harmonic spectrum can serve as a measure of the structure of these laser-induced potentials.