Influence of light absorption in the interaction of asymmetric elegant Hermite-cosh-Gaussian laser beams with collisionless magnetized plasma

Abstract

In the present paper, an analysis of self-focusing of asymmetric elegant Hermite-cosh-Gaussian laser beams having transverse electromagnetic (TEMmn) modes with mode indices m = 0 and n = 0, 2, and 4 in magnetized plasma has been presented. The nonlinearity in the effective dielectric function of plasma considered herein is mainly due to the ponderomotive mechanism. The nonlinear coupled differential equations for beam width parameters in both x and y dimensions of the beams are established by using Wentzel–Kramers–Brillouin and paraxial approximations through a parabolic equation approach. The behavior of beam width parameters with the dimensionless distance of propagation is presented graphically at different parameters of plasma and those of general beam's family considered. Specifically, complexity in beam width parameters is highlighted through the influence of light absorption, mode index, and decentered parameter. The results show that two unlike decentered parameters in transverse dimensions of the beam change beam-widths considerably at higher order mode indices. Absorption gives an important role in complexity of beam width parameters in transverse dimensions of the beam.

Nonlinear Propagation of Gaussian Laser Beam in Magnetized Plasma: Effect of Oblique Magnetic Field

“…An importance of asymmetry in the beam profile has been highlighted by Vhanmore et al [19,20] in collisionless magnetized plasma. An influence of light absorption in magnetized plasma has been reported by Vhanmore et al [21] for asymmetric laser beams. The review of literature highlights the fact that to study the influence of magnetic field on propagation of laser beam, the direction is an important factor in addition to its strength.…”

Studies of Terahertz Sources and Their Applications

“…It has been concluded that, when transverse plasma density is homogeneous, its focusing ability is robust than that of the hollow Gaussian laser. Vhanmore et al [43] used asymmetric elegant Hermite-cosh-Gaussian to study the self-focusing in magnetized plasma. Kumar et al [44] analytically studied relativistic self-focusing and particle-in-cell simulations, which reveals that the self-focusing is less sensitive to laser amplitude variation in deeper plasma channels for millimeter range plasma channels present scheme is being valid.…”

Self-Focusing of Gaussian Laser Beam in an Axially Magnetized Plasma

“…The nonlinear measure of dielectric function is varying according to physical circumstances but its dependence on intensity of input beam is a common feature. For collisionless magnetized plasma 𝜺 𝟎 and 𝝓 can be written as [19][20][21], Here 𝝎 𝒑 , 𝝎 𝐜 and 𝝎 are the electron plasma frequency, electron cyclotron frequency and frequency of laser used, 𝒆 and 𝒎 are the charge and rest mass of electron respectively, 𝑴 is the mass of ion, 𝒏 𝟎 is the equilibrium plasma density, 𝑲 𝑩 is the Boltzmann constant, 𝑻 𝟎 is an equilibrium plasma temperature, 𝑩 𝟎 is an external magnetic field which is assumed to be applied along (forward) as well as opposite (reverse) to the direction of propagation of laser beam, 𝝈 is the parameter associated with magnetization. For the case of forward (reverse) magnetization 𝝈 = +𝟏 (𝝈 = −𝟏).…”