Laser-controlled optics using near-resonance nonlinear dispersion in gaseous media

Nonlinear dispersion in gaseous media is analyzed from the standpoint of its potential applications to laser-controlled optics. Refractive optics as well as real-time holographic optics are considered. The nonlinear refractive index for a gaseous medium is calculated for near-resonance conditions using the density-matrix formalism, including gaseous collisions. A coupled-wave theory is used to analyze interaction in a laser-controlled, real-time holographic grating. It is shown that the collision-dominated, rather than the collision-free regime, is the more useful for laser-controlled optics applications. The effect of diffusion in the gaseous medium is incorporated in the analysis. Expressions for intensity requirements are derived for laser-controlled holographic optical applications as well as for refractive-optics applications.