We present a simple method for creating a maximal coherent superposition of N states (a superposition state with equal amplitudes) in a robust way. We show that in the adiabatic limit the robustness of the population transfer out of a single state to the superposition state is equivalent to stimulated Raman adiabatic passage. As is typical for schemes based upon population trapping the method is insensitive to radiative decay from excited states.

• Received 2 August 2000

DOI:https://doi.org/10.1103/PhysRevA.63.043401