Resonant excitation of the upper hybrid wave by relativistic cross focusing of two laser beams

Abstract

AbstractThis article presents the resonant excitation of the upper hybrid wave (UHW) by cross focusing of two high power laser beams in a collisionless hot magnetoplasma; taking into account the relativistic nonlinearity. The electric vectors of the two beams are polarized along uniform static magnetic field and the beams propagate perpendicular to the static magnetic field. The resonant excitation of the UHW occurs when the frequency difference (FD) of the two laser beams and difference of their propagation vector satisfy the dispersion relation corresponding to the UHW. It has been observed that the power associated with the excited UHW, which depends on the background electron concentration, magnetic field and the intensity of the two laser beams, becomes drastically modified with the distance of propagation. The effect of the excited UHW at the FD on the acceleration of electrons has also been discussed. The amplitude of the UHW, excited by two high power laser beams and the electron energy are also calculated. This study is relevant in heating of plasma near the upper hybrid frequency as well as electron acceleration. The results are presented for typical laser plasma parameters.