Abstract:
When light interacts with a medium, it is either transmitted or absorbed following
the laws of reflection and refraction, but a tiny fraction is scattered by inhomogeneties in
the medium. These inhomogeneties can be static or dynamic. Scattering from defects and
dislocations in a crystal is considered as static and light scatters elastically from them.
Fluctuations in the optical inhomogeneties in the medium that are associated with lattice
vibrations (phonons or vibrons) are the examples of dynamic scatterers. They inealstically
scatter the light. Raman scattering is an inelastic scattering of light which occurs due to
the interaction of the light with elementary excitations (quasi-particles) of the matter such
as optical phonons, polaritons, magnons, plasmons and vibrons in liquids and gases.
