The paper theoretically studies the propagation regimes of narrow (millimeter) laser beams in a Kerr-nonlinear turbulent medium, which simulates the evolution of light inhomogeneities generated under multiple filamentation of high-power laser pulses in corresponding media, by methods of diffraction-beam tubes and diffraction rays. Three propagation regimes are found: self-focusing with generation of a nonlinear focus (beam collapse), self-channeling over a limited distance, and turbulent propagation. An equation for squared beam effective radius is derived, which is of interest for practical applications in nonlinear atmospheric optics.
A.A. Zemlyanov (Wed,) studied this question.