Deflection of laser-excited atoms by an electric field

An experiment is analyzed in which an atomic beam in a collinear, counterstreaming laser beam is deflected by an inhomogeneous dc electric field. The force acting on the translational motion of the atom is found. This describes a modification of the deflection due to the laser. The atom tends to decouple itself from the laser, but a method is suggested for a continuous recoupling. This can result in a large difference in the scattering between atoms coupled to the laser and atoms uncoupled. The applicability to isotope separation is pointed out.