View source for Brillouin scattering

'''Brillouin scattering''', named after [[Léon Brillouin]], occurs when light, passing through a transparent medium interacts with that medium's periodic spatial & temporal variations producing that medium's refractive index.

== Description ==

As described in optics, the index of refraction of a transparent material changes under deformation (compression-distension or shear-skewing).

The result of the interaction between the light-wave and the carrier-deformation wave is that a fraction of the transmitted light-wave changes its momentum (thus its frequency and energy) in preferential directions, as if by diffraction caused by an oscillating 3-dimensional diffraction grating.

If the medium is a solid crystal, a macromolecular chain condensate or a viscous liquid or gas, then the low frequency atomic-chain-deformation waves within the transmitting medium (not the transmitted electro-magnetic wave) in the carrier (represented as a quasiparticle) could be for example:

* Mass oscillation (acoustic) modes (called [[Phonon|phonons]]);
* Charge displacement modes (in dielectrics, called [[Polaron|polarons]]);
* Magnetic spin oscillation modes (in magnetic materials, called [[Magnon|magnons]]).

== See also ==

* [[Light]]
* [[Raman scattering]]
* [[Scattering]]

== External links ==

* [https://en.wikipedia.org/wiki/Brillouin_scattering Brillouin scattering] @ Wikipedia


[[Category:Light]]
[[Category:Physics]]