Effects of energy absorption on Raman amplification in plasma

Bernhard Ersfeld, John Farmer, Gaurav Raj, Dino A. Jaroszynski, DA Jaroszynski (Editor), A Rousse (Editor)

Research output: Contribution to conferencePaper

Abstract

Stimulated Raman backscattering in plasma has been suggested as a way to amplify short laser pulses to intensities not limited by damage thresholds as in chirped pulse amplification using conventional media. Energy is transferred between two transverse electromagnetic waves, pump and probe, through the parametric interaction with a longitudinal Langmuir wave that is ponderomotively excited by their beat wave. The increase of the plasma temperature due to collisional absorption of the pump wave modifies the dispersion of the Langmuir wave: firstly, its resonance frequency rises (Bohm-Gross shift), and secondly, Landau damping sets in. The frequency shift acts in a similar way to a chirp of the pump frequency, or a density ramp: different spectral components of the probe satisfy the resonance condition at different times. This limits their growth, while increasing the bandwidth of the amplifier, thus leading to superradiant amplification. Landau damping may shorten the probe pulse, but reduces the amplification efficiency. We investigate these effects analytically and using numerical simulations in order to assess their importance in experimental demonstrations, and the possibility of applications.

Conference

ConferenceConference on Harnessing Relativistic Plasma Waves as Novel Radiation Sources From Terahertz to X-Rays and Beyond
CountryCzech Republic
CityPrague
Period21/04/0923/04/09

Fingerprint

energy absorption
Landau damping
pumps
probes
pulses
plasma temperature
yield point
chirp
ramps
frequency shift
synchronism
backscattering
electromagnetic radiation
amplifiers
bandwidth
shift
lasers
simulation
interactions
energy

Keywords

  • Raman amplification
  • thermal effects
  • chirp
  • absorption

Cite this

Ersfeld, B., Farmer, J., Raj, G., Jaroszynski, D. A., Jaroszynski, DA. (Ed.), & Rousse, A. (Ed.) (2009). Effects of energy absorption on Raman amplification in plasma. Paper presented at Conference on Harnessing Relativistic Plasma Waves as Novel Radiation Sources From Terahertz to X-Rays and Beyond, Prague, Czech Republic. https://doi.org/10.1117/12.820618
Ersfeld, Bernhard ; Farmer, John ; Raj, Gaurav ; Jaroszynski, Dino A. ; Jaroszynski, DA (Editor) ; Rousse, A (Editor). / Effects of energy absorption on Raman amplification in plasma. Paper presented at Conference on Harnessing Relativistic Plasma Waves as Novel Radiation Sources From Terahertz to X-Rays and Beyond, Prague, Czech Republic.
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title = "Effects of energy absorption on Raman amplification in plasma",
abstract = "Stimulated Raman backscattering in plasma has been suggested as a way to amplify short laser pulses to intensities not limited by damage thresholds as in chirped pulse amplification using conventional media. Energy is transferred between two transverse electromagnetic waves, pump and probe, through the parametric interaction with a longitudinal Langmuir wave that is ponderomotively excited by their beat wave. The increase of the plasma temperature due to collisional absorption of the pump wave modifies the dispersion of the Langmuir wave: firstly, its resonance frequency rises (Bohm-Gross shift), and secondly, Landau damping sets in. The frequency shift acts in a similar way to a chirp of the pump frequency, or a density ramp: different spectral components of the probe satisfy the resonance condition at different times. This limits their growth, while increasing the bandwidth of the amplifier, thus leading to superradiant amplification. Landau damping may shorten the probe pulse, but reduces the amplification efficiency. We investigate these effects analytically and using numerical simulations in order to assess their importance in experimental demonstrations, and the possibility of applications.",
keywords = "Raman amplification, thermal effects, chirp , absorption",
author = "Bernhard Ersfeld and John Farmer and Gaurav Raj and Jaroszynski, {Dino A.} and DA Jaroszynski and A Rousse",
year = "2009",
doi = "10.1117/12.820618",
language = "English",
note = "Conference on Harnessing Relativistic Plasma Waves as Novel Radiation Sources From Terahertz to X-Rays and Beyond ; Conference date: 21-04-2009 Through 23-04-2009",

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Ersfeld, B, Farmer, J, Raj, G, Jaroszynski, DA, Jaroszynski, DA (ed.) & Rousse, A (ed.) 2009, 'Effects of energy absorption on Raman amplification in plasma' Paper presented at Conference on Harnessing Relativistic Plasma Waves as Novel Radiation Sources From Terahertz to X-Rays and Beyond, Prague, Czech Republic, 21/04/09 - 23/04/09, . https://doi.org/10.1117/12.820618

Effects of energy absorption on Raman amplification in plasma. / Ersfeld, Bernhard; Farmer, John; Raj, Gaurav; Jaroszynski, Dino A.; Jaroszynski, DA (Editor); Rousse, A (Editor).

2009. Paper presented at Conference on Harnessing Relativistic Plasma Waves as Novel Radiation Sources From Terahertz to X-Rays and Beyond, Prague, Czech Republic.

Research output: Contribution to conferencePaper

TY - CONF

T1 - Effects of energy absorption on Raman amplification in plasma

AU - Ersfeld, Bernhard

AU - Farmer, John

AU - Raj, Gaurav

AU - Jaroszynski, Dino A.

A2 - Jaroszynski, DA

A2 - Rousse, A

PY - 2009

Y1 - 2009

N2 - Stimulated Raman backscattering in plasma has been suggested as a way to amplify short laser pulses to intensities not limited by damage thresholds as in chirped pulse amplification using conventional media. Energy is transferred between two transverse electromagnetic waves, pump and probe, through the parametric interaction with a longitudinal Langmuir wave that is ponderomotively excited by their beat wave. The increase of the plasma temperature due to collisional absorption of the pump wave modifies the dispersion of the Langmuir wave: firstly, its resonance frequency rises (Bohm-Gross shift), and secondly, Landau damping sets in. The frequency shift acts in a similar way to a chirp of the pump frequency, or a density ramp: different spectral components of the probe satisfy the resonance condition at different times. This limits their growth, while increasing the bandwidth of the amplifier, thus leading to superradiant amplification. Landau damping may shorten the probe pulse, but reduces the amplification efficiency. We investigate these effects analytically and using numerical simulations in order to assess their importance in experimental demonstrations, and the possibility of applications.

AB - Stimulated Raman backscattering in plasma has been suggested as a way to amplify short laser pulses to intensities not limited by damage thresholds as in chirped pulse amplification using conventional media. Energy is transferred between two transverse electromagnetic waves, pump and probe, through the parametric interaction with a longitudinal Langmuir wave that is ponderomotively excited by their beat wave. The increase of the plasma temperature due to collisional absorption of the pump wave modifies the dispersion of the Langmuir wave: firstly, its resonance frequency rises (Bohm-Gross shift), and secondly, Landau damping sets in. The frequency shift acts in a similar way to a chirp of the pump frequency, or a density ramp: different spectral components of the probe satisfy the resonance condition at different times. This limits their growth, while increasing the bandwidth of the amplifier, thus leading to superradiant amplification. Landau damping may shorten the probe pulse, but reduces the amplification efficiency. We investigate these effects analytically and using numerical simulations in order to assess their importance in experimental demonstrations, and the possibility of applications.

KW - Raman amplification

KW - thermal effects

KW - chirp

KW - absorption

U2 - 10.1117/12.820618

DO - 10.1117/12.820618

M3 - Paper

ER -

Ersfeld B, Farmer J, Raj G, Jaroszynski DA, Jaroszynski DA, (ed.), Rousse A, (ed.). Effects of energy absorption on Raman amplification in plasma. 2009. Paper presented at Conference on Harnessing Relativistic Plasma Waves as Novel Radiation Sources From Terahertz to X-Rays and Beyond, Prague, Czech Republic. https://doi.org/10.1117/12.820618