HIGH-RESOLUTION MULTIPHOTON IONIZATION AND DISSOCIATION OF H2 AND D2 MOLECULES IN INTENSE LASER FIELDS

We report on the multiphoton ionization and dissociation of hydrogen and deuterium molecules in intense (8 x 10(11)-4 x 10(13) W/cm2) laser fields. The investigations were performed with the second harmonics of two different laser systems, a 50-ps neodymium-doped yttrium lithium fluoride and a 10-ns neodymium doped yttrium aluminum garnet laser. Measurements included energy-resolved photoelectron and mass spectroscopy. In addition, we report on a measurement of the dynamics of different above-threshold dissociation branching ratios for H-2+ and D2+ over a wide range of laser intensities. Our results support the dressed-molecule picture at least qualitatively, but differences do exist with the quantitative predictions.