Multiphoton population dynamics in a three-level lambda system and the related light-scattering spectrum

We generalize our analytic approach (Berent M and Parzynski R 2009 Phys. Rev. A 80 033834) to include the effect of strong depopulation of the initial state when considering the multiphoton population transfer and scattering of low-frequency light by a three-level system in the lambda-type configuration. We discuss the quality of the approximations made, i.e. the adiabatic and generalized rotating-wave approximations.