Coherent population trapping resonance on the 87Rb D1 line in the field of circularly polarized counterpropagating waves

The study of the previously proposed method for improving the parameters of the coherent population trapping resonance on the 87 Rb D 1 line using two counterpropagating bichromatic fields with orthogonal circular polarizations is continued. The method consists in elimination of trap states existing in the conventional σ + measurement scheme and limiting the resonance amplitude. The resonance parameters are studied in a wide range of pump radiation intensities and in various configurations implementing the σ + - σ − scheme.