An efficient scheme for controlling the photoionization of H₂⁺ is investigated by using an accurate 3D time-dependent wavepacket method. Compared with the one-color filed, the ionization probability of H₂⁺ is greatly enhanced in the two-color (790-395 nm) field. By manipulating the relative carrier-envelope phase of the two-color field, the highest asymmetry modulation relative to the laser polarization reaches up to 52% in the ionization of H₂⁺. In our control scheme, the subcycle waveform of the two-color field is manipulated to control the maixmum field amplitudes in the positive and negative directions. The sensitive dependence of the subcycle waveform in the asymmetric ionization of H₂⁺ is explained by tracing the laser-driven motion of the electron in the dressed double well potential. In addition, the basic mechanism behind the enhanced ionization of the molecule is revealed, which provides a practical guide for the optical control of the ionization dynamics in future experiments.

quantum control  /  time-dependent wave packet approach  /  photoionization  /  laser field