An efficient scheme for controlling the spatial distribution of the Raman amplification process in a medium consisting of three-level atoms in a Λ configuration is considered. The pump field is a combination of two Laguerre-Gaussian beams and a Gaussian beam with the same frequency. By adjusting the topological charge, intensity, and phase of the pump field components as well as the two-photon detuning, the spatial distribution of the generated Stokes field can be manipulated. It is shown that by optimizing these optical parameters, efficient control over the spatial distribution of Raman amplification is achievable.
Ikonnikov et al. (Mon,) studied this question.