Nonlinear Ramsey resonance of the number of excited particles

An analysis is made of the interaction of three spatially separate standing Gaussian waves with an atomic beam. The case of a Doppler-broadened transition is considered. An expression is obtained for the correction to the resonance in the number of excited particles, the width of the correction being inversely proportional to the transit time between the waves. The analysis is carried out for a weak field. Numerical calculations of the amplitude and profile of the resonance are reported. The optimal (in respect of the field intensity) conditions for the observation of this resonance are determined.