Abstract:

Theoretical investigation on the propagation characteristics of a new class of laser beams known as multi Gaussian (M.G) laser beams has been presented. To investigate the linear characteristics, propagation of the laser beam in vacuum has been considered. Whereas, the nonlinear characteristics have been investigated in plasmas. Optical nonlinearity of the plasma has been modeled by relativistic mass nonlinearity of the plasma electrons in the field of laser beam. Formulation is based on finding the semi analytical solution of the wave equation for the slowly varying envelope of the laser beam. Particularly, the dynamical evolutions of the beam width and longitudinal phase of the laser beam have been investigated in detail.

Key words: self-focusing, multi Gaussian, self phase modulation, self-channeling