Molecular dynamics in attosecond-duration intense-field pulses using a tandem accelerator

摘要

External perturbation of intramolecular eletric fields can result in structural changes that influence energy, entropy and molecular dynamics. We have probed the ionization and fragmentation dynamics of triatomic and polyatomic molecules induced by intense, transient fields gnerated in fast (50-100 MeV) collisoons with Si~(q+) (q chemical bounds 3-8) ions, and by using a laser. In the former case, at an impact parameter of approx 3A, the target molecule experimences an attosecond-duration field whose magnitude (approx 0.05 V/A) matches that induced by intense (10~(13) W/cm~2) laser light. The temporal and directional properties of the two fields are very different: the linearly-polarized hight yields a fixed field direction wherease the ion-induced field is time-dependent. Moreover, the ion-induced fields are of attosecond duration whereas the laser-induced ones last for picosceconds. We explore how the dissociatve ionization patterns measured in our expeirments reflect these temporal and directional differences.