skip to main content

Title: Higher-order paraxial theory of the propagation of ring rippled laser beam in plasma: Relativistic ponderomotive regime

This article presents higher-order paraxial theory (non-paraxial theory) for the ring ripple formation on an intense Gaussian laser beam and its propagation in plasma, taking into account the relativistic-ponderomotive nonlinearity. The intensity dependent dielectric constant of the plasma has been determined for the main laser beam and ring ripple superimposed on the main laser beam. The dielectric constant of the plasma is modified due to the contribution of the electric field vector of ring ripple. Nonlinear differential equations have been formulated to examine the growth of ring ripple in plasma, self focusing of main laser beam, and ring rippled laser beam in plasma using higher-order paraxial theory. These equations have been solved numerically for different laser intensities and plasma frequencies. The well established experimental laser and plasma parameters are used in numerical calculation. It is observed that the focusing of the laser beams (main and ring rippled) becomes fast in the nonparaxial region by expanding the eikonal and other relevant quantities up to the fourth power of r. The splitted profile of laser beam in the plasma is observed due to uneven focusing/defocusing of the axial and off-axial rays. The growths of ring ripple increase when the laser beam intensitymore » increases. Furthermore, the intensity profile of ring rippled laser beam gets modified due to the contribution of growth rate.« less
Authors:
;  [1] ;  [2] ;  [3]
  1. Department of Physics, Laser-Plasma Computational Laboratory, DAV PG College, Dehradun, Uttarakhand (India)
  2. Department of Physics and Material Science and Engineering, Jaypee Institute of Information Technology, Uttar Pradesh (India)
  3. Department of Physics, College of Science, UAE University, PO Box 17551 Al-Ain (United Arab Emirates)
Publication Date:
OSTI Identifier:
22410296
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 5; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; DIFFERENTIAL EQUATIONS; EIKONAL APPROXIMATION; ELECTRIC FIELDS; FOCUSING; LANGMUIR FREQUENCY; LASER RADIATION; NONLINEAR PROBLEMS; PERMITTIVITY; PHOTON BEAMS; PLASMA; PONDEROMOTIVE FORCE; RELATIVISTIC RANGE