Growth rate and gain of stimulated Brillouin scattering considering nonlinear Landau damping due to particle trapping

Stimulated Brillouin scattering of an electromagnetic wave is investigated analytically in a dissipative magnetized plasma in the presence of negative ions. With an increase in the number of negative ions (maintaining quasi-neutrality), it is found that the growth rate of ion-acoustic waves decreases very slowly up to 50% concentration (i.e. half of the total ionic contribution) of negative ions. Further increase in the number density of negative ions beyond 50% results in a sharp fall in growth rate.

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Suppression of Stimulated Brillouin Scattering by Increased Landau Damping in Multiple-Ion-Species Hohlraum Plasmas

Physical Review Letters ◽

10.1103/physrevlett.100.105001 ◽

2008 ◽

Vol 100 (10) ◽

Cited By ~ 30

Author(s):

P. Neumayer ◽

R. L. Berger ◽

L. Divol ◽

D. H. Froula ◽

R. A. London ◽

...

Keyword(s):

Brillouin Scattering ◽

Stimulated Brillouin Scattering ◽

Landau Damping ◽

Stimulated Brillouin ◽

Ion Species

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Suppression of stimulated Brillouin scattering in laser beam hot spots

Laser and Particle Beams ◽

10.1017/s026303460999036x ◽

2009 ◽

Vol 27 (4) ◽

pp. 619-627 ◽

Cited By ~ 18

Author(s):

R.P. Sharma ◽

Prerana Sharma ◽

Shivani Rajput ◽

A.K. Bhardwaj

Keyword(s):

Laser Beam ◽

Brillouin Scattering ◽

Collisionless Plasma ◽

Stimulated Brillouin Scattering ◽

Landau Damping ◽

Beam Radius ◽

Plasma Parameters ◽

Power Flux ◽

Ion Acoustic Wave ◽

Stimulated Brillouin

AbstractIn this article, filamentation of a high power laser beam in hot collisionless plasma is investigated considering the ponderomotive nonlinearity. We have studied the effect of self focusing (filamentation) of the laser beam on the localization of ion acoustic wave (IAW) and on stimulated Brillouin scattering (SBS) process. The nonlinear coupling between the laser beam and IAW results in the modification of the Eigen frequency of IAW; consequently, enhanced Landau damping of IAW and a modified mismatch factor in SBS process occur. Due to enhanced Landau damping, there is a reduction in the intensity of IAW wave, and the SBS process gets suppressed. For the typical laser plasma parameters: the laser power flux = 1016 W/cm2, laser beam radius (r0) = 12 µm, n/ncr = 0.11, and (Te/Ti) = 10, the SBS reflectivity is found to be suppressed approximately by 10%.

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Stimulated Brillouin scattering of whistler waves in low-density collisionless plasmas

Journal of Plasma Physics ◽

10.1017/s0022377800011843 ◽

1986 ◽

Vol 36 (3) ◽

pp. 371-377

Author(s):

S. Guha ◽

C. Basu

Keyword(s):

Growth Rate ◽

Ponderomotive Force ◽

Brillouin Scattering ◽

Negative Ions ◽

Stimulated Brillouin Scattering ◽

Low Density ◽

Whistler Waves ◽

Ionospheric Modification ◽

Collisionless Plasmas ◽

Stimulated Brillouin

We present a theoretical investigation of stimulated Brillouin scattering (SBS) of whistler waves in low-density collisionless plasmas in the presence of negative ions and incorporating the effect of the ponderomotive force on electrons. It is found that the growth rate of the excited ion quasi-mode decreases with increasing concentration of negative ions. The effect of negative ions on the SBS of the whistler waves during the ionospheric modification is discussed.

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