Probe-intensity dependence of velocity-selective polarization spectra at the rubidium D2 manifold and comparison with a rate-equation calculation
J. Flores-Mijangos, F. Ramírez-Martínez, Ricardo Colín‐Rodríguez +2 more
We present a detailed study of the effect of a strong and circularly polarized coupling beam on a probe beam locked to a hyperfine transition of the rubidium ${D}_{2}$ manifold. Experiments were carried out in the co- and counterpropagating configurations. Counterpropagating beams are used to study the effect of the probe beam intensity on absorption and polarization spectra. These data are compared with results of a rate-equation calculation. The absorption spectra show very clear indication of saturation, with different saturation intensities for each atomic line. The slope of the dispersionlike profile of the polarization signal increases with the intensity of the probe beam. These results are in very good agreement with the calculation. Experimental absorption and polarization spectra in the copropagating configuration are also well reproduced by the rate-equation calculation. The dispersion profiles in the polarization signal can be used to lock the coupling laser frequency at well defined frequencies.
Physical Review A•Apr 7, 2014•7 citations