Probing orbital symmetries and ionization dynamics of simple molecules with femtosecond laser pulses

It is shown that by measuring the angular distributions of fragmented ions of simple molecules by sub-10 fs laser pulses at intensities in the non-sequential double ionization regime the electron density of the highest occupied molecular orbital can be probed directly. It is also shown that using a single laser pulse, from the kinetic energy release of the fragmented ions following the double ionization of H2, the time interval between the two ionizations can be controlled and determined to sub-fs accuracy by varying the pulse duration and laser intensity. Furthermore, using a pump-probe scheme the time evolution of the vibrational wave packet on two potential surfaces can be mapped directly using two sub-10 fs lasers. Theoretical models are used to explain these recent experiments.