Nonlinear structure of the electromagnetic waves in underdense plasmas

The interaction of a high-frequency electromagnetic wave with a collisionless unmagnetized nonisothermal plasma, taking into account the ponderomotive force per unit volume acting on the plasma electrons, is studied. The electron density distribution is found. Obtaining the nonlinear differential and integral equations for the electric field and using the Maxwell equations, we investigate the electric and magnetic field profiles in plasma. It is shown that the profiles of the electric and magnetic field departure from a sinusoidal shape and the electron density becomes highly peaked for the higher electromagnetic energy flux