One and two-colour studies of the dissociative ionization and Coulomb explosion of H2 with intense Ti:sapphire laser pulses

Phase control of the spatial asymmetry of the dissociative ionization channel, H+H+, of molecular hydrogen has been achieved by superposing interferometrically sub-100 fs, Ti:sapphire laser pulses at the fundamental and second harmonic frequency. The counterintuitive asymmetry previously observed with longer, less intense Nd:YLF laser pulses and HD molecules has been reproduced. However, phase modulation of total ionization and dissociation rates was not discernible. In order to further understand the process, a comprehensive study of appearance intensities, kinetic energy releases and angular distributions has been undertaken at each frequency.