Self-Focusing of Hermite-Cosh-Gaussian Laser Beams in Plasma under Density Transition

Abstract

Self-focusing of Hermite-Cosh-Gaussian (HChG) laser beam in plasma under density transition has been discussed here. The field distribution in the medium is expressed in terms of beam-width parameters and decentered parameter. The differential equations for the beam-width parameters are established by a parabolic wave equation approach under paraxial approximation. To overcome the defocusing, localized upward plasma density ramp is considered, so that the laser beam is focused on a small spot size. Plasma density ramp plays an important role in reducing the defocusing effect and maintaining the focal spot size up to several Rayleigh lengths. To discuss the nature of self-focusing, the behaviour of beam-width parameters with dimensionless distance of propagation for various values of decentered parameters is examined by numerical estimates. The results are presented graphically and the effect of plasma density ramp and decentered parameter on self-focusing of the beams has been discussed.

Propagation properties of higher-order cosine-hyperbolic-Gaussian beams in a chiral medium

“…The ChGBs have been largely researched for their potential application in many fields, e.g. micromanipulation of particles, optical trapping, telecommunications, highpower laser, and plasma physics (Patil et al 2012;Kaur et al 2017;Wani and Kant 2014;Konar et al 2007;Mahajan et al 2018;Patil et al 2009;Gill 2010;Chen and Dai 2009) . A more generalized expression of the ChGB called the higher-order cosh-Gaussian beam (HOChGB) was introduced by Zhou and Zheng (Zhou and Zheng 2009) in 2009.…”

Paraxial propagation of Hermite cosine-hyperbolic-Gaussian beams in a chiral medium

“…As b or m increases, the peak intensity of the beam becomes more acentric, and by selecting appropriate value of the beam parameter, a HChGB can describe the Gaussian beam, Hermite-Gaussian beam, and the cosh-Gaussian beam. The shape variability of the HChGB has stimulated extensive applications, e.g., micromanipulation of particles, optical trapping, telecommunications, high-power laser, and plasma physics [15][16][17][18][19][20][21][22]. So far, the propagation features of HChGB in many optical systems have been reported.…”

Nonlinear interaction of intense left- and right-hand polarized laser pulse with hot magnetized plasma

“…Nanda et al. (Wani & Kant 2014) considered self-focusing of a Hermite–Cosh–Gaussian laser beam under density transition for different modes in a plasma.…”

“…Also, impacts of plasma electron temperature, relative density parameter and intensity parameter on the propagation of the laser beam have been studied. Nanda et al (Wani & Kant 2014) considered self-focusing of a Hermite-Cosh-Gaussian laser beam under density transition for different modes in a plasma. Khachatrian & Sukhorukov (1971) presented some aspects of thermal self-focusing.…”