Analytical investigation on domain of decentered parameter for self-focusing of Hermite-cosh-Gaussian laser beam in collisional plasma

Abstract

In the present paper, an analytically investigated domain of decentered parameter and its effect on the self-focusing of Hermit-cosh-Gaussian (HChG) laser beams in a collisional plasma have been studied theoretically. The nonlinearity in the dielectric constant of plasma arising due to the nonuniform heating of carriers along the wavefront of the laser beam has been employed in the present investigation. The nonlinear differential equation of beam width parameter for various laser modes of HChG beam is obtained by following the standard Akhamanov's parabolic equation approach under Wentzel-Kramers-Brillouin and paraxial approximations. The analytical treatment has enabled us to define three distinct regions: self-focusing, self-trapping and defocusing, which are presented graphically.

Effect of Critical Beam Radius on Self-focusing of cosh-Gaussian Laser Beams in Collisionless Magnetized Plasma

“…Equation ( 15) is significant equation, which throws light on condition for self trapping of laser beam, for following analysis one may show that self trapping is determined by critical power but it is also determined by corrosponding ρ 0+min . Therefore following the same line of analysis, [24] one may determine ρ 0+min analytically as,…”

Self-focusing/defocusing of skew-cosh-Gaussian laser beam for collisional plasma

“…, where ω p is the plasma electron frequency in the absence of the beam and ω p = √ 4π n e e 2 /m , where and e are the density of plasma electrons in the absence of the laser beam, and charge on electrons, respectively. The term ϕ (EE * ) represents a field-dependent dielectric function for collisional plasma [14]:…”

“…The non-uniform heating of the carrier mechanism is observed to be effective rather than the ponderomotive force mechanism in a steady state. As a consequence of the self-induced inhomogeneity in the dielectric function of the plasma, the effective dielectric function modifies remarkably, and the self-focusing and defocusing of the beams are produced [12][13][14]. Recently, some laser beam profiles have been explored for the studies of self-focusing and defocusing, such as Gaussian beams [15][16][17], cosh-Gaussian (ChG) beams [18][19][20][21], Hermite-ChG beams [22][23][24][25], among others, in collisional plasmas.…”

On the Exploration of q Parameter in Propagation Dynamics of q-Gaussian Laser Beam in Underdense Collisional Plasma

“…The effective dielectric function gets modified significantly, due to selfinduced nonlinearity dependence on the intensity of the laser beam [8]. The propagation of different kinds of laser beam profiles like Gaussian beams [9,10], Cosh-Gaussian beams [11][12][13], Hermite -Gaussian beams [14], Hermite-cosh-Gaussian (HChG) beams [15][16][17] etc., in the collisional plasmas has attracted the attention of the many researchers. One should note that in all above beams Gaussian remains intact.…”