Detection of a coherent population trapping resonance in a beam of 87Rb atoms by the Ramsey method

Formation of a coherent population trapping (CPT) resonance is studied in the interaction of a beam of ⁸⁷Rb atoms with two spatially separated domains of the dichromatic field. Various resonance excitation schemes are compared depending on the choice of operation transitions and type of the polarisation scheme. In the case of a single-velocity atomic beam, the dependence of the CPT resonance profile is studied as a function of principal parameters of the system: beam velocity, distance between optical fields, laser beam dimensions and intensities, and applied permanent magnetic field. Influence of the atomic beam angular divergence and residual beam velocity spread on the resonance quality parameter is estimated.