Plasma density fluctuations driven by a randomized laser beam and application to self-smoothing

Abstract
The multiple scattering of random laser beams on self-induced density fluctuations is responsible for the modification of the spatial and temporal coherence properties of the transmitted light. We investigate within a statistical approach the excitation of density fluctuations by randomized laser beams. Their spectrum is derived and their level is estimated as a few percents. The thermal effects are discussed. We characterize the evolution of the density perturbation level in time and along the propagation axis.