Raman scattering and synchrotron x-ray diffraction studies on rare-earth based functional oxides

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.