The Probe Transmission Spectra of ⁸⁷Rb in an Operating Magneto-Optical Trap in the Presence of an Ionizing Laser

The influence of an ionizing laser on the pump-probe spectra of ⁸⁷Rb over the transition 5²S_1/2,F=2 →5²P_3/2,F'=3 is experimentally studied in an operating magneto-optical trap. These spectral features, including gain peak, a dispersion-like structure and absorption peak, become weak as the intensity of the ionizing laser increases. Moreover, the profiles of the absorption peak and gain peak vary as the ionizing laser intensity changes. Such results indicate that there is more than one component in the two features and that each component has different dependences on the number of ⁸⁷Rb atoms.