Theoretical analysis of a moving three-level atom interacting slantingly with a standing wave laser field

A momentum transfer of a moving three-level atom interacting slantingly with a standing wave laser field was analyzed. The results show that a stimulated Raman transition is dominated, when some conditions are met by both the atom and the light field. If the light field relative by the atom is a π/2 pulse light, the atom will be in a coherent superposition state after interaction. The one state is the same as the initial state of the atom, and the other is a new state in which the degrees of internal atomic freedom and the center-of-mass momentum of the atom are all changed, especially, the momentum is changed by twice single-photon recoil momentum. Nevertheless, the probability of the atom in two states is equal. If this mechanism is used for atomic wave interferometry, it is possible that atomic packets are coherently split.