Radiation and Scattering Processes

Sune R. Svanberg

Sune R. Svanberg

Sune R. Svanberg

Sune R. Svanberg

Igor' M Bel'dyugin, E M Zemskov

A theoretical study is made of the stimulated scattering of radiation whose spectrum is much wider than the frequency of a vibrational transition in the scattering medium. It is shown that the efficiency of the scattering process then depends strongly on the statistical properties of the incident (pump) radiation.

B. A. Veklenko

The evolution of a quantized electromagnetic field in a thermally excited dispersion medium is determined by two scattering channels. The coherent channel is formed exclusively by the elastic scattering of quanta. The incoherent channel, along with elastic scattering processes, necessarily contains inelastic scattering processes, including induced radiation. Interference between the channels is absent because of the orthogonality of the wave functions of the medium in its final states, which correspond to different scattering channels. Therefore, in an excited medium, interference processes that are not described by its refractive index may arise. An interference pattern of this kind can be formed, in particular, as a result of the superposition of the resonance radiation incident on an excited medium and the radiation reflected from this medium. In this case, the conventional perturbation theory proves to be inadequate.