Ionization Modulation Of H By Two Time-Delayed Strong Ir Pulses

The ionization modulation of the hydrogen atom is investigated theoretically by the numerical solution to the time-dependent Schrodinger equation and the strong-field-approximation method. Considering a pair of identical but time-delayed one-cycle infrared laser pulses, we find that the total ionization yield is modulated by the time delay between the two pulses. We show that the modulation is mainly due to the interference of electron wave packets in the continuum states respectively generated by each of the two pulses. In this tunneling regime, we identify some similarities to and differences from the usual quantum control of electron transition that is in the perturbation regime. Finally, we also extend our study of ionization modulation to the one-multicycle-laser-pulse case with different wavelengths in the tunneling regime.