MULTIZONE OPTICAL RAMSEY RESONANCE WITH TRAVELING WAVES

A general equation for the interaction of atoms with many separated traveling waves is introduced, and the oscillating terms corresponding to the Ramsey fringes are found in the equation. The features of the multizone Ramsey resonance are quite comprehensible with the aid of the diagrammatic representation of the atomic beam and laser fields. The resonance condition and the narrowing effect of the fringe width are discussed. Using the intercombination line of a Ca atom, the multizone Ramsey resonances of up to ten separated fields were demonstrated. With the ten separated fields, the Ramsey fringes with a contrast of 130% to the saturation dip could be obtained at a relatively small excitation power.