Particle-in-cell Simulations of Raman Laser Amplification in Ionizing Plasmas

doi:https://doi.org/10.2172/814693

Title: Particle-in-cell Simulations of Raman Laser Amplification in Ionizing Plasmas

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Abstract

By using the amplifying laser pulse in a plasma-based backward Raman laser amplifier to generate the plasma by photo-ionization of a gas simultaneous with the amplification process, possible instabilities of the pumping laser pulse can be avoided. Particle-in-cell simulations are used to study this amplification mechanism, and earlier results using more elementary models of the Raman interaction are verified [D.S. Clark and N.J. Fisch, Phys. Plasmas, 9 (6): 2772-2780, 2002]. The effects (unique to amplification in ionizing plasmas and not included in previous simulations) of blue-shifting of the pump and seed laser pulses and the generation of a wake are observed not significantly to impact the amplification process. As expected theoretically, the peak output intensity is found to be limited to I {approx} 10{sup 17} W/cm{sup 2} by forward Raman scattering of the amplifying seed. The integrity of the ionization front of the seed pulse against the development of a possible transverse modulation instability is also demonstrated.

Authors:: Clark, Daniel S; Fisch, Nathaniel J

Publication Date:: 2003-06-27

Research Org.:: Princeton Plasma Physics Lab., NJ (US)

Sponsoring Org.:: USDOE Office of Science (SC) (US)

OSTI Identifier:: 814693

Report Number(s):: PPPL-3829
TRN: US0304313

DOE Contract Number:: AC02-76CH03073

Resource Type:: Technical Report

Resource Relation:: Other Information: PBD: 27 Jun 2003

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AMPLIFICATION; AMPLIFIERS; INSTABILITY; IONIZATION; LASERS; MODULATION; PLASMA; PUMPING; SCATTERING; SEEDS; COMPUTER SIMULATION; LASER-PLASMA INTERACTIONS

Citation Formats


                    Clark, Daniel S, and Fisch, Nathaniel J. Particle-in-cell Simulations of Raman Laser Amplification in Ionizing Plasmas.  United States: N. p., 2003. 
        Web.  doi:10.2172/814693.

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                    Clark, Daniel S, & Fisch, Nathaniel J. Particle-in-cell Simulations of Raman Laser Amplification in Ionizing Plasmas.  United States.  https://doi.org/10.2172/814693

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                    Clark, Daniel S, and Fisch, Nathaniel J. Fri .  
        "Particle-in-cell Simulations of Raman Laser Amplification in Ionizing Plasmas".  United States.  https://doi.org/10.2172/814693.  https://www.osti.gov/servlets/purl/814693.

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@article{osti_814693,

  title        = {Particle-in-cell Simulations of Raman Laser Amplification in Ionizing Plasmas},

  author       = {Clark, Daniel S and Fisch, Nathaniel J},

  abstractNote = {By using the amplifying laser pulse in a plasma-based backward Raman laser amplifier to generate the plasma by photo-ionization of a gas simultaneous with the amplification process, possible instabilities of the pumping laser pulse can be avoided. Particle-in-cell simulations are used to study this amplification mechanism, and earlier results using more elementary models of the Raman interaction are verified [D.S. Clark and N.J. Fisch, Phys. Plasmas, 9 (6): 2772-2780, 2002]. The effects (unique to amplification in ionizing plasmas and not included in previous simulations) of blue-shifting of the pump and seed laser pulses and the generation of a wake are observed not significantly to impact the amplification process. As expected theoretically, the peak output intensity is found to be limited to I {approx} 10{sup 17} W/cm{sup 2} by forward Raman scattering of the amplifying seed. The integrity of the ionization front of the seed pulse against the development of a possible transverse modulation instability is also demonstrated.},

  doi          = {10.2172/814693},

  url          = {https://www.osti.gov/biblio/814693},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {2003},

  month        = {6}

}

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