Generation of a plasma wave and second harmonic in a magnetoplasma

Abstract

This paper presents an investigation of the generation of a plasma wave and a second-harmonic electromagnetic wave in a collilsionless hot magnetoplasma by a Gaussian EM beam (pump wave) propagating perpendicular to a static magnetic field in the ordinary mode. Because of the Gaussian intensity distribution of the EM wave, the ponderomotive force becomes finite and the electrons become redistributed; the electron density gradient (so created) and the intensity gradient of the EM wave lead to the generation of a plasma wave at the pump-wave frequency. The intensity of the magnetic field significantly affects the plasma-wave generation. When the pump-wave frequency is equal to the upper-hybrid frequency, resonant excitation of the plasma wave occurs. The plasma wave interacting with the pump wave leads to the generation of a second-harmonic electromagnetic wave. Moreover, as the pump wave propagates in the plasma, its self-focusing occurs; consequently, the plasma-wave and the second-harmonic generation become drastically affected.