Observation of doubly dressed states in cold atoms

We report an experimental observation of doubly dressed states in ${}^{87}\mathrm{Rb}$ atoms cooled and confined in a magneto-optical trap. The doubly dressed states are produced by a strong-coupling laser and a moderate pump laser in a three-level atomic configuration. The absorption spectrum of a weak probe laser reveals a three-peaked spectral profile that can be interpreted by a dressed-state picture and agrees well with calculations based on the density-matrix equations.