Effect of orbital angular momentum on self-focusing of Laguerre–Gaussian laser beams in magnetized plasma

This paper presents the propagation of high-power twisted Laguerre–Gaussian beams (LGBs) carrying orbital angular momentum in plasma. A paraxial-like approach to the phenomenon of self-focusing in the vicinity of the intensity maximum is adopted for both radial and vortex mode indices of LGBs. The nonlinear differential equation for the beam-width parameter of LGBs, as a function of the dimensionless distance of propagation in magnetized plasma, is obtained and solved numerically by using the fourth-order Runge–Kutta method. For the numerical appreciation of the results, the influence of orbital angular momentum (OAM) and the strength of the magnetic field on critical curves are specifically considered. A comparison is made between two different polarizations, i.e., left circular polarization (LCP) and right circular polarization (RCP), to emphasize the response of the medium.