Nonlinear interaction of a Gaussian electromagnetic beam with an electrostatic upper hybrid wave: Generation of electrostatic lower hybrid wave

Abstract

This paper presents an investigation of the nonlinear interaction of a Gaussian electromagnetic (EM) beam with an electrostatic upper hybrid wave in a collisionless magnetoplasma. The EM beam is assumed to be propagating in the ordinary mode, having a nonuniform intensity distribution (along its wave front) in a plane transverse to the direction of propagation. Because of the Gaussian intensity distribution of the EM beam, a time-independent component of the ponderomotive force becomes finite and this leads to a coupling between the pump EM beam and the electrostatic upper hybrid wave. This coupling is so strong that the weak electrostatic upper hybrid wave gets excited. The excited electrostatic upper hybrid wave may again interact with the pump EM beam and lead to the generation of an electrostatic lower hybrid wave of significant power.