Nonlinear interaction of quadruple Gaussian laser beams with collisional plasmas with nonlinear absorption: self focusing and self phase modulation

This study explores how an intense laser beam with a quadruple Gaussian profile behaves as it travels through a collisional plasma that exhibits nonlinear absorption. The Drude model is used to describe the plasma’s dielectric properties under this nonlinearity. The analysis relies on numerically solving the nonlinear Schrödinger wave equation (NSWE) for the laser beam’s field, employing the moment theory approach within the W.K.B approximation. Through simulations, the researchers investigate how various laser and plasma parameters influence the beam’s propagation characteristics. They specifically focus on how the beam’s width and longitudinal phase change as it travels through the plasma.