Temporal separation of H2 double-ionization channels using intense ultrashort 10-fs laser pulses

Double ionization channels of H-2 are separated in the time domain using ultrashort 10-fs laser pulses in the 10(13)-10(15) W cm(-2) intensity range. Charge resonance enhanced ionization does not contribute anymore to double ionization because the H-2 (+) ion does not have enough time to stretch up to the critical internuclear distance. Using a pump-probe excitation scheme, this process is shown to be very sensitive for the detection of pre- and post-pulses situated at a few tens of femtoseconds from the maximum pulse envelope.