Impact of linear absorption on self-focusing of Gaussian laser beam in collisional plasma

The authors have investigated impact of linear absorption on self-focusing of Gaussian laser beam in collisional plasma. The nonlinearity in dielectric constant considered herein is mainly due to the elastic electron–ion collisions. A second order differential equation of dimensionless beam width parameter has been derived and solved numerically. It is observed that absorption plays a vital role in self-focusing of laser beams and weakens the stationary oscillatory character of beam-width parameter with distance of propagation. We have also considered the effect of intensity, relative density and parameter characterizing nature of collisions on propagation characteristics.

► Effect of linear absorption on self-focusing of laser beam in collisional plasma is explored. ► Equation for beam width parameter is established using the parabolic equation approach. ► Absorption weakens the stationary oscillatory focusing character of beam width parameter.