Electron acceleration and spatio-temporal variation of Laguerre-Gaussian laser pulse in relativistic plasma

In this paper, the investigation of spatial and temporal dynamics of high power Laguerre-Gaussian laser pulse propagating inside the plasma medium has been presented. The effect of relativistic nonlinearity has been taken into account. The variation in the mass of the relativistic moving electrons introduces perturbation in the dielectric function and results in the generation of the electron plasma wave. This excited electron plasma wave with a high field acts as a wakefield that accelerates the electrons along with it. The variation in the spatial and temporal width of the Laguerre-Gaussian laser pulse has been studied by using the method of moments approach. The solution for the spatial and temporal width parameters of the laser pulse has been obtained numerically by solving two nonlinear coupled differential equations. The electric field of the generated electron plasma wave is then used to calculate the energy gained by the electrons. The spatio-temporal dynamics and energy gain have been studied for different modes of the Laguerre-Gaussian laser pulse. From the investigation, it has been observed that the (0, 2) mode of the Laguerre-Gaussian laser pulse is more suitable for higher energy gain.