SPATIAL CONTROL OF Na EXCITATION BY MEANS OF INTERFERENCE DUE TO AUTLER-TOWNES EFFECT

We present the results of detailed calculations, which show that spatial distribution of atomic excitation can be controlled in a three-level scheme by creating Ramsey interference employing the Autler-Townes effect. The first excitation step is realized by strong and tightly focused pump field creating spatially-varying dressed states. The second excitation step can take place at two spatial locations (Landau-Zener points), where the second laser field is resonant with one of the dressed states. Thus, two alternative excitation pathways to the final level exist, whose constructive or destructive interference determines the transition probability at the second Landau-Zener region. In this way, the spatial distribution of populations of excited states can be controlled by varying the laser frequencies and intensities. Moreover, moderate detunings of the pump field are favorable for the observation of interference effects. The experimental realization of the idea is in progress.