Control of Electron Localization in the Asymmetric Dissociation of Hydrogen Molecular Ions H2+ Driven by a Two-Color Field

The electron localization of hydrogen molecular ions (H2+) driven by a two-color field is investigated by solving the time-dependent Schrödinger equation in the non-Born–Oppenheimer approximation. The results indicate that the degree of electron localization is highly sensitive to both the time delay of the two-color field and the intensity of the control laser pulse. We compared the evolutions of both molecular nuclear and electronic wave packets under one-color versus two-color fields. It is found that a control field with a proper intensity has a slight influence on the dissociation process while significantly affecting the electron transition process. The coupling region around R = 5.2 a.u. of the control field plays an important role in the electron localization process, despite potential Stark shifts. Control field intensities in the range of 9 × 1012 to 2 × 1013 W/cm2 are found to be effective. Applying the control pulse with a 17 fs time delay and an intensity of 2 × 1013 W/cm2 results in a high percent electron control efficiency of 83%. Further investigation shows that effective control of electron localization in the asymmetric dissociation can still be achieved by altering the relative phase of the two-color field while keeping the time delay constant.