Coherent population transfer of ground-state atoms into Rydberg states

The technique of stimulated Raman adiabatic passage (STIRAP) is used to excite laser-cooled rubidium atoms from the Rb-85 5S(1/2) ground state to the 44D(5/2) Rydberg state through the 5P(3/2) state. The utilized double-STIRAP scheme allows for an accurate determination of the absolute excitation efficiency. Experimental data are compared with results of a detailed theoretical model, and good agreement is found. It is concluded that at the center of the excitation region an excitation efficiency of 70% is achieved.