Three Wave Mixing and Four Wave Scattering Processes in Laser-Plasma Interaction

A nonlinear fluid description for the parameter processes has been derived. The linear instability analyses about three wave mixing process ω₀ →ω_s1 + ω_s2 and four wave scattering process ω₀→ω_s + ω_P1 + ω_P2 have been made. Correspondent backward or side scattering light waves emitted from mentioned processes may provide valuable information for the diagnostic of plasma parameters.