Cars spectroscopy

Theoretical, experimental, and applied areas of coherent anti-Stokes Raman scattering (CARS) are examined, along with an investigation of the related processes Raman-induced Kerr effect and stimulated Raman scattering. The theoretical underpinnings of third-order nonlinear processes are detailed, and the spectral properties of CARS are obtained from nonlinear source polarization. The birth and growth of the signal electromagnetic wave are explored, along with energy processes within the material. The application of CARS to practical temperature and concentration measurements in reactive media is described, with discussion made of spatial resolution, detectivity, line contour, and saturation. The possible resonance enhancement of CARS is investigated for use in sensitive trace species detection and for high resolution molecular spectroscopy. Finally, ONERA CARS usage for combustion diagnostics and resonant spectroscopy in gases is outlined.