Nonlinear optical effects in aerosols

The physical aspects of the nonlinear optics of scattering media are examined with particular attention given to phenomena encountered in the propagation of intense laser beams through a turbid atmosphere. Results are presented of Mie scattering theoretical calculations of the spatial structure of light fields within weakly scattering spheres and of the ponderomotive action of an intense optical wave on transparent particles, which results in particle acceleration, coagulation, orientation and surface oscillations. Investigations of the nonlinear effects of pulsed laser radiation on the solid components of absorbing particles are then considered, with attention given to unsteady acoustic self-focusing, thermal blooming, solid evaporation and gas ionization. The kinetics of the evaporation of radiatively heated drops is then examined for drops typical of atmospheric aerosols, and nonlinear thermal interactions of laser beams with water aerosols are examined, with consideration given to the formation and motions of the illumination wave, the structural and optical properties of the illumination channel and secondary effects of recondensation and optical wave distortion.