Effect of orbital angular momentum on dust-ion-acoustic waves in a superthermal plasma

Abstract

Laser or electromagnetic radiation, in general, interacts with plasma in very interesting ways. In most cases, they induce orbital angular momentum (OAM) in such plasmas due to their polarization effects. Dust-ion-acoustic waves (DIAWs) with immovable dust particles are studied with the effect of rotation produced due to laser or electromagnetic interaction. The electrons are considered in the non-Maxwellian limit, with inertial ions and static dust grains possessing negative charges. Fluid theory is employed for obtaining the linear paraxial equation with regard to ion density perturbations. The fundamental Gaussian and Laguerre Gaussian (LG) beam solutions are talked over with the later being proved to be the source for OAM. By calculating the electrostatic potential for such linear waves, the components of the electric field with respect to the LG potential are shown. Finally, the energy density equation is used to calculate the OAM associated with DIAWs. The Laguerre Gauss mode is numerically shown to have greatly changed by varying the values of relevant plasma parameters, such as the electron superthermality parameter, radial and angular mode numbers, beam waist, and azimuthal angle. The present results may be useful in apprehending dust-ion-acoustic wave excitation due to Brillouin backscattering phenomenon of laser light interacting with plasma.