NONLINEARITY AND ASYMMETRY OF RAMAN-SCATTERING IN CRYSTALS

A new type of asymmetry of the spontaneous Raman scattering (ASRS) is considered for multilayered crystals epsilon-GaSe (D3h6-symmetry) where not only the probabilities of light scattering are different for scattering to the right and left directions but also the phonon frequencies and phonon half-widths differ. A new ASRS has been discovered for Si-crystals (O(h)7) after UV irradiation also. We showed that interface modes, chaotic behavior of the nonlinear dynamical systems and the Duffing potential renormalization driven by the noise can describe and explain the peculiarities of ASRS and give rise to ASRS in crystals. An asymmetry of the spontaneous Raman scattering in crystals represents conveniently and clearly the experimental physical model for the study of chaos in nonlinear optics.