Potential Well Dynamics of Self Focusing of Quadruple Gaussian Laser Beams in Thermal Quantum Plasma
Naveen Gupta, Sanjeev Kumar, Suman Choudhry, S.B. Bhardwaj and Sandeep Kumar
This paper presents theoretical study on self-action effects of intense laser beams interacting with fusion plasmas. Particularly the phenomena associated with the nonlinear refraction of the laser beam have been investigated in detail. In order to see the effect of uniformity of the illumination over the beam phase fronts on its propagation characteristics the irradiance profile of the beam has been modeled by quadruple Gaussian (Q.G) profile. Following Variational theory approach, the nonlinear partial differential equation (PDE) for the beam envelope has been reduced to a set of coupled ordinary differential equations for the evolution of beam width and axial phase. The equations so obtained have been solved numerically to envision the effect of laser as well as medium parameters on the propagation characteristics of the laser beam.
Keywords: Self-focusing, phase shift, self trapping, variational theory, quantum plasma