Effect of low-energy electron interference on strong-field molecular ionization

By using a three-dimensional time-dependent Schrodinger equation, we calculate alignment-dependent ionization of model diatomic molecules subjected to an intense laser field with different internuclear distances. It is found that the ionization probability shows oscillatory behavior with respect to the angle between the laser polarization direction and the molecular axis for large internuclear distances. Comparing with the results obtained by Ammosov-Delone-Krainov (ADK) theory and S-matrix theory, the intriguing phenomenon can be attributed to the two-center interference effect of low-energy photoelectrons. Furthermore, it is shown that ADK theory is not applicable for the investigation of molecular ionization for large internuclear distances.National Basic Research Program of China [2013CB922201]; NNSF of China [11274050, 11334009, 11425414, 11374197, 11447114, 11504215]SCI(E)EIARTICLEchen_jing@iapcm.ac.cn29